[1] Stereo was invented by .
A.
John Barber
B.
Tim Berners-Lee
C.
Alan Blumlein
D.
David Brewster
Ans:
Alan Blumlein
Explanation :
Modern stereophonic technology was invented in the 1930s by British engineer Alan Blumlein at Electric and Musical Industries in London. Modern stereophonic technology was invented in the 1930s by British engineer Alan Blumlein at EMI, who patented stereo records, stereo films, and also surround sound. In early 1931, Blumlein and his wife were at a local cinema.
[2] How much mechanical work must be done to completely melt 1 gram of ice at 0°C?
A.
4.2 J
B.
80 J
C.
336 J
D.
2268 J
Ans:
80 J
Explanation :
When water at 0 degree Celsius freezes, each gram of water gives off 80 calories. The temperature of the water stays at 0 degree C until every drop has frozen. When ice at 0 degree Celsius melts, it absorbs an equal amount of heat-80 calories for each gram of ice—and its temperature remains unchanged until it has completely melted.
[3] A bullet is fired from a rifle which recoils after firing. The ratio of kinetic energy of the rifle to that of the bullet is –
A.
zero
B.
one
C.
less than one
D.
more than one
Ans:
zero
Explanation :
The rifle and bullet have zero momentum and zero kinetic energy to start with. When the trigger is pulled, the bullet gains some momentum in the forward direction, but this is canceled by the rifle's backward momentum, so the total momentum is still zero. The kinetic energies of the gun and bullet are both positive scalars, however, and do not cancel.
[4] At low temperature, Lead behaves as a :
A.
Semi conductor
B.
Super conductor
C.
Insulator
D.
Conductor
Ans:
Super conductor
Explanation :
Lead exhibit superconducting phase transitions at low temperatures of 7.2 Kelvin. This discovery was made in 1913. At this temperature (known as critical temperature), the electrical resistivity of lead drops to zero. The transition is so sudden and complete that it appears to be a transition to a different phase of matter; this superconducting phase is described by the BCS theory.
[5] Which of the following is the best conductor of electricity?
A.
Zinc
B.
Copper
C.
Gold
D.
Silver
Ans:
Silver
Explanation :
Copper: 9% less conductive than silver; aluminium is 10% less conductive than copper; while steel is the least conductive among the given options. The most electrically conductive metal is silver.
[6] At what temperature are the temperature on Celsius and Fahrenheit scales equal?
A.
273° Celsius
B.
-273° Celsius
C.
-40° Celsius
D.
40° Celsius
Ans:
-40° Celsius
Explanation :
If C is the temperature in Celsius and F is the temperature in Fahrenheit then, C F - 32 = S 9 They are equal at -40° (minus 40 degrees), because if we convert the readings of Celsius and Fahrenheit, we will have: Celsius to Fahrenheit (-40°C x 9/5) +32 = -72 + 32 = -40°F. Fahrenheit to Celsius (-40°F - 32°) x 5/9 = (-72) x 5/9 = -40°C.
[7] The electric charge is stored in a device called:
A.
Inductor
B.
Capacitor
C.
Resister
D.
Transformer
Ans:
Capacitor
Explanation :
A capacitor is a passive two-terminal electronic component that stores electrical energy in an electric field. The effect of a capacitor is known as capacitance.
[8] SI unit for the surface tension is .
A.
kg/m2
B.
kg/m3
C.
N/m
D.
kg/m
Ans:
N/m
Explanation :
Surface tension, represented by the symbol γ (alternatively σ or T), is measured in force per unit length. Its SI unit is newton per meter but the cgs unit of dyne per centimeter is also used.
[9] The density of the liquid when heated –
A.
decreases
B.
increases
C.
does not change
D.
may increase of decrease depending on pressure
Ans:
decreases
Explanation :
The mass density of a material varies with temperature and pressure. Increasing the temperature of a substance (with some exceptions) decreases its density by increasing the volume of that substance. In most materials, heating the bottom of a fluid results in convection of the heat from bottom to top of the fluid due to the decrease of the density of the heated fluid.
[10] The distance between node and adjacent antinodes is 30 cm. The wavelength is -
A.
30 cm.
B.
90 cm.
C.
120 cm.
D.
60 cm.
Ans:
60 cm.
Explanation :
A node is a point along a standing wave where the wave has minimal amplitude. The opposite of a node is an antinode, a point where the amplitude of the standing wave is a maximum.
[11] When a bar magnet is cut into two equal halves, the pole strength of each piece –
A.
becomes double
B.
becomes half
C.
becomes zero
D.
remains the same
Ans:
remains the same
Explanation :
The poles remains same whether the magnet is cut into two equal half or more and also pole strength remains same but magnetic moment reduces due to decrease in the length of the magnet. If a bar magnet is suspended by a thread, it will come to rest in a position close to the north-south direction. The end of the magnetic toward the north is called north pole (N-poled of the magnet and the other end the south pole (S-pole).
[12] A new technology which provides the ability to create an artificial world and have people interact with it is called –
A.
Televirtuality
B.
Virtual reality
C.
Alternate reality
D.
3-D reality
Ans:
Virtual reality
Explanation :
Virtual reality (VR) is a term that applies to computer-simulated environments that can simulate physical presence in places in the real world, as well as in imaginary worlds. Most current virtual reality environments are primarily visual experiences, displayed either on a computer screen or through special stereoscopic displays, but some simulations include additional sensory information, such as sound through speakers or headphones.
[13] A proton is identical to _.
A.
the nucleus of helium
B.
the nucleus of a hydrogen atom
C.
an alpha-particle
D.
a beta particle
Ans:
a beta particle
Explanation :
0
[14] What should a person on a freely rotating turn table do to decrease his (angular) speed?
A.
Bring his hands together
B.
Raise his hands up
C.
Spread his hands outwards
D.
Sit down with raised hands
Ans:
Spread his hands outwards
Explanation :
The answer is related to the conservation of angular momentum. The person on the rotating table will maintain approximately the same angular momentum during the spin. If he moves his arms in, it will reduce the rotational inertia by reducing the distance of the mass of her arms and hands from the axis of rotation.
[15] In a rechargeable cell what kind of energy is stored within the cell?
A.
Electrical energy
B.
Potential energy
C.
Chemical energy
D.
Kinetic energy
Ans:
Chemical energy
Explanation :
In electricity, a battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. A battery is a device that converts chemical energy directly to electrical energy. It consists of a number of voltaic cells; each voltaic cell consists of two half-cells connected in series by a conductive electrolyte containing anions and cations.
[16] Which one of the following lenses should be used to correct the defect of astigmatism?
A.
Cylindrical lens
B.
Concave lens
C.
Convex lens
D.
Bifocal lens
Ans:
Cylindrical lens
Explanation :
Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina. This may be due to an irregular or toric curvature of the cornea or lens. The two types of astigmatism are regular and irregular. Irregular astigmatism is often caused by a corneal scar or scattering in the crystalline lens, and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses.
[17] Danger signals are generally red as red light –
A.
is least bright
B.
undergoes least deviation
C.
has lowest velocity
D.
gives comfort to eye
Ans:
undergoes least deviation
Explanation :
The primary reason why the colour red is used for danger signals is that red light is scattered the least by air molecules. The effect of scattering is inversely related to the fourth power of the wavelength of a colour. Therefore blue which has the least wavelength of all the visible radiations is scattered the most and red which has the highest wavelength of all the colours we can see is scattered the least.
[18] A simple microscope consists of :
A.
a short focus convex lens
B.
a long focus convex lens
C.
a short focus concave lens
D.
a long focus concave lens
Ans:
a short focus convex lens
Explanation :
Simple microscope - light microscope consisting of a short focus single convex lens is used to produce an enlarged image. The magnifying glass was invented by Roger Bacon in 1250. In the original 'simple' microscopes, a single light path went through the object viewed and one lens, increasing the visibility of the object by some amount (magnification).
[19] A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to –
A.
Outward pull on him
B.
Inertia of motion
C.
Change in momentum
D.
Change in acceleration
Ans:
Inertia of motion
Explanation :
This is inertia of direction. It is the ability of body to be in a state of direction of motion for example sun holds planets in a fixed elliptical path this is one of the examples of inertia of direction. Inertia of direction is non-existent however inertia only apply to a body at rest or moving with a constant velocity. It is the property possessed by a body to resist change. In other way we can say that if a body moves in a particular direction under the action of a force and if the force is removed then the will continue to move in the same direction unless stopped under the action of another opposing force for a body at rest it under the inertia of rest whereas inertia of motion is for bodies in motion.
[20] When pressure is increased the melting point of ice –
A.
increases
B.
does not change
C.
decreases
D.
depends on the impurities in the ice
Ans:
decreases
Explanation :
In this case, if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point — allowing more solid to become liquid and hence when we increase pressure, the melting point of ice decreases because of the inversal relationship between the pressure and melting point of ice.
[21] What apparatus is used to locate a submerged object?
A.
Radar
B.
Sonar
C.
Quasar
D.
Pulsar
Ans:
Sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.
[22] The instrument which uses sound waves to measure the depth of oceans is –
A.
Radar
B.
Sonar
C.
Altimeter
D.
Venturimeter
Ans:
Sonar
Explanation :
The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations.
[23] One Kilowatt hour is equal to—
A.
3.6 Mega Joule
B.
3.8 Mega Joule
C.
3.2 Mega Joule
D.
4.0 Mega Joule
Ans:
3.6 Mega Joule
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
Modern stereophonic technology was invented in the 1930s by British engineer Alan Blumlein at Electric and Musical Industries in London. Modern stereophonic technology was invented in the 1930s by British engineer Alan Blumlein at EMI, who patented stereo records, stereo films, and also surround sound. In early 1931, Blumlein and his wife were at a local cinema.
[2] How much mechanical work must be done to completely melt 1 gram of ice at 0°C?
A.
4.2 J
B.
80 J
C.
336 J
D.
2268 J
Ans:
80 J
Explanation :
When water at 0 degree Celsius freezes, each gram of water gives off 80 calories. The temperature of the water stays at 0 degree C until every drop has frozen. When ice at 0 degree Celsius melts, it absorbs an equal amount of heat-80 calories for each gram of ice—and its temperature remains unchanged until it has completely melted.
[3] A bullet is fired from a rifle which recoils after firing. The ratio of kinetic energy of the rifle to that of the bullet is –
A.
zero
B.
one
C.
less than one
D.
more than one
Ans:
zero
Explanation :
The rifle and bullet have zero momentum and zero kinetic energy to start with. When the trigger is pulled, the bullet gains some momentum in the forward direction, but this is canceled by the rifle's backward momentum, so the total momentum is still zero. The kinetic energies of the gun and bullet are both positive scalars, however, and do not cancel.
[4] At low temperature, Lead behaves as a :
A.
Semi conductor
B.
Super conductor
C.
Insulator
D.
Conductor
Ans:
Super conductor
Explanation :
Lead exhibit superconducting phase transitions at low temperatures of 7.2 Kelvin. This discovery was made in 1913. At this temperature (known as critical temperature), the electrical resistivity of lead drops to zero. The transition is so sudden and complete that it appears to be a transition to a different phase of matter; this superconducting phase is described by the BCS theory.
[5] Which of the following is the best conductor of electricity?
A.
Zinc
B.
Copper
C.
Gold
D.
Silver
Ans:
Silver
Explanation :
Copper: 9% less conductive than silver; aluminium is 10% less conductive than copper; while steel is the least conductive among the given options. The most electrically conductive metal is silver.
[6] At what temperature are the temperature on Celsius and Fahrenheit scales equal?
A.
273° Celsius
B.
-273° Celsius
C.
-40° Celsius
D.
40° Celsius
Ans:
-40° Celsius
Explanation :
If C is the temperature in Celsius and F is the temperature in Fahrenheit then, C F - 32 = S 9 They are equal at -40° (minus 40 degrees), because if we convert the readings of Celsius and Fahrenheit, we will have: Celsius to Fahrenheit (-40°C x 9/5) +32 = -72 + 32 = -40°F. Fahrenheit to Celsius (-40°F - 32°) x 5/9 = (-72) x 5/9 = -40°C.
[7] The electric charge is stored in a device called:
A.
Inductor
B.
Capacitor
C.
Resister
D.
Transformer
Ans:
Capacitor
Explanation :
A capacitor is a passive two-terminal electronic component that stores electrical energy in an electric field. The effect of a capacitor is known as capacitance.
[8] SI unit for the surface tension is .
A.
kg/m2
B.
kg/m3
C.
N/m
D.
kg/m
Ans:
N/m
Explanation :
Surface tension, represented by the symbol γ (alternatively σ or T), is measured in force per unit length. Its SI unit is newton per meter but the cgs unit of dyne per centimeter is also used.
[9] The density of the liquid when heated –
A.
decreases
B.
increases
C.
does not change
D.
may increase of decrease depending on pressure
Ans:
decreases
Explanation :
The mass density of a material varies with temperature and pressure. Increasing the temperature of a substance (with some exceptions) decreases its density by increasing the volume of that substance. In most materials, heating the bottom of a fluid results in convection of the heat from bottom to top of the fluid due to the decrease of the density of the heated fluid.
[10] The distance between node and adjacent antinodes is 30 cm. The wavelength is -
A.
30 cm.
B.
90 cm.
C.
120 cm.
D.
60 cm.
Ans:
60 cm.
Explanation :
A node is a point along a standing wave where the wave has minimal amplitude. The opposite of a node is an antinode, a point where the amplitude of the standing wave is a maximum.
[11] When a bar magnet is cut into two equal halves, the pole strength of each piece –
A.
becomes double
B.
becomes half
C.
becomes zero
D.
remains the same
Ans:
remains the same
Explanation :
The poles remains same whether the magnet is cut into two equal half or more and also pole strength remains same but magnetic moment reduces due to decrease in the length of the magnet. If a bar magnet is suspended by a thread, it will come to rest in a position close to the north-south direction. The end of the magnetic toward the north is called north pole (N-poled of the magnet and the other end the south pole (S-pole).
[12] A new technology which provides the ability to create an artificial world and have people interact with it is called –
A.
Televirtuality
B.
Virtual reality
C.
Alternate reality
D.
3-D reality
Ans:
Virtual reality
Explanation :
Virtual reality (VR) is a term that applies to computer-simulated environments that can simulate physical presence in places in the real world, as well as in imaginary worlds. Most current virtual reality environments are primarily visual experiences, displayed either on a computer screen or through special stereoscopic displays, but some simulations include additional sensory information, such as sound through speakers or headphones.
[13] A proton is identical to _.
A.
the nucleus of helium
B.
the nucleus of a hydrogen atom
C.
an alpha-particle
D.
a beta particle
Ans:
a beta particle
Explanation :
0
[14] What should a person on a freely rotating turn table do to decrease his (angular) speed?
A.
Bring his hands together
B.
Raise his hands up
C.
Spread his hands outwards
D.
Sit down with raised hands
Ans:
Spread his hands outwards
Explanation :
The answer is related to the conservation of angular momentum. The person on the rotating table will maintain approximately the same angular momentum during the spin. If he moves his arms in, it will reduce the rotational inertia by reducing the distance of the mass of her arms and hands from the axis of rotation.
[15] In a rechargeable cell what kind of energy is stored within the cell?
A.
Electrical energy
B.
Potential energy
C.
Chemical energy
D.
Kinetic energy
Ans:
Chemical energy
Explanation :
In electricity, a battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. A battery is a device that converts chemical energy directly to electrical energy. It consists of a number of voltaic cells; each voltaic cell consists of two half-cells connected in series by a conductive electrolyte containing anions and cations.
[16] Which one of the following lenses should be used to correct the defect of astigmatism?
A.
Cylindrical lens
B.
Concave lens
C.
Convex lens
D.
Bifocal lens
Ans:
Cylindrical lens
Explanation :
Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina. This may be due to an irregular or toric curvature of the cornea or lens. The two types of astigmatism are regular and irregular. Irregular astigmatism is often caused by a corneal scar or scattering in the crystalline lens, and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses.
[17] Danger signals are generally red as red light –
A.
is least bright
B.
undergoes least deviation
C.
has lowest velocity
D.
gives comfort to eye
Ans:
undergoes least deviation
Explanation :
The primary reason why the colour red is used for danger signals is that red light is scattered the least by air molecules. The effect of scattering is inversely related to the fourth power of the wavelength of a colour. Therefore blue which has the least wavelength of all the visible radiations is scattered the most and red which has the highest wavelength of all the colours we can see is scattered the least.
[18] A simple microscope consists of :
A.
a short focus convex lens
B.
a long focus convex lens
C.
a short focus concave lens
D.
a long focus concave lens
Ans:
a short focus convex lens
Explanation :
Simple microscope - light microscope consisting of a short focus single convex lens is used to produce an enlarged image. The magnifying glass was invented by Roger Bacon in 1250. In the original 'simple' microscopes, a single light path went through the object viewed and one lens, increasing the visibility of the object by some amount (magnification).
[19] A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to –
A.
Outward pull on him
B.
Inertia of motion
C.
Change in momentum
D.
Change in acceleration
Ans:
Inertia of motion
Explanation :
This is inertia of direction. It is the ability of body to be in a state of direction of motion for example sun holds planets in a fixed elliptical path this is one of the examples of inertia of direction. Inertia of direction is non-existent however inertia only apply to a body at rest or moving with a constant velocity. It is the property possessed by a body to resist change. In other way we can say that if a body moves in a particular direction under the action of a force and if the force is removed then the will continue to move in the same direction unless stopped under the action of another opposing force for a body at rest it under the inertia of rest whereas inertia of motion is for bodies in motion.
[20] When pressure is increased the melting point of ice –
A.
increases
B.
does not change
C.
decreases
D.
depends on the impurities in the ice
Ans:
decreases
Explanation :
In this case, if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point — allowing more solid to become liquid and hence when we increase pressure, the melting point of ice decreases because of the inversal relationship between the pressure and melting point of ice.
[21] What apparatus is used to locate a submerged object?
A.
Radar
B.
Sonar
C.
Quasar
D.
Pulsar
Ans:
Sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.
[22] The instrument which uses sound waves to measure the depth of oceans is –
A.
Radar
B.
Sonar
C.
Altimeter
D.
Venturimeter
Ans:
Sonar
Explanation :
The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations.
[23] One Kilowatt hour is equal to—
A.
3.6 Mega Joule
B.
3.8 Mega Joule
C.
3.2 Mega Joule
D.
4.0 Mega Joule
Ans:
3.6 Mega Joule
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
The rifle and bullet have zero momentum and zero kinetic energy to start with. When the trigger is pulled, the bullet gains some momentum in the forward direction, but this is canceled by the rifle's backward momentum, so the total momentum is still zero. The kinetic energies of the gun and bullet are both positive scalars, however, and do not cancel.
[4] At low temperature, Lead behaves as a :
A.
Semi conductor
B.
Super conductor
C.
Insulator
D.
Conductor
Ans:
Super conductor
Explanation :
Lead exhibit superconducting phase transitions at low temperatures of 7.2 Kelvin. This discovery was made in 1913. At this temperature (known as critical temperature), the electrical resistivity of lead drops to zero. The transition is so sudden and complete that it appears to be a transition to a different phase of matter; this superconducting phase is described by the BCS theory.
[5] Which of the following is the best conductor of electricity?
A.
Zinc
B.
Copper
C.
Gold
D.
Silver
Ans:
Silver
Explanation :
Copper: 9% less conductive than silver; aluminium is 10% less conductive than copper; while steel is the least conductive among the given options. The most electrically conductive metal is silver.
[6] At what temperature are the temperature on Celsius and Fahrenheit scales equal?
A.
273° Celsius
B.
-273° Celsius
C.
-40° Celsius
D.
40° Celsius
Ans:
-40° Celsius
Explanation :
If C is the temperature in Celsius and F is the temperature in Fahrenheit then, C F - 32 = S 9 They are equal at -40° (minus 40 degrees), because if we convert the readings of Celsius and Fahrenheit, we will have: Celsius to Fahrenheit (-40°C x 9/5) +32 = -72 + 32 = -40°F. Fahrenheit to Celsius (-40°F - 32°) x 5/9 = (-72) x 5/9 = -40°C.
[7] The electric charge is stored in a device called:
A.
Inductor
B.
Capacitor
C.
Resister
D.
Transformer
Ans:
Capacitor
Explanation :
A capacitor is a passive two-terminal electronic component that stores electrical energy in an electric field. The effect of a capacitor is known as capacitance.
[8] SI unit for the surface tension is .
A.
kg/m2
B.
kg/m3
C.
N/m
D.
kg/m
Ans:
N/m
Explanation :
Surface tension, represented by the symbol γ (alternatively σ or T), is measured in force per unit length. Its SI unit is newton per meter but the cgs unit of dyne per centimeter is also used.
[9] The density of the liquid when heated –
A.
decreases
B.
increases
C.
does not change
D.
may increase of decrease depending on pressure
Ans:
decreases
Explanation :
The mass density of a material varies with temperature and pressure. Increasing the temperature of a substance (with some exceptions) decreases its density by increasing the volume of that substance. In most materials, heating the bottom of a fluid results in convection of the heat from bottom to top of the fluid due to the decrease of the density of the heated fluid.
[10] The distance between node and adjacent antinodes is 30 cm. The wavelength is -
A.
30 cm.
B.
90 cm.
C.
120 cm.
D.
60 cm.
Ans:
60 cm.
Explanation :
A node is a point along a standing wave where the wave has minimal amplitude. The opposite of a node is an antinode, a point where the amplitude of the standing wave is a maximum.
[11] When a bar magnet is cut into two equal halves, the pole strength of each piece –
A.
becomes double
B.
becomes half
C.
becomes zero
D.
remains the same
Ans:
remains the same
Explanation :
The poles remains same whether the magnet is cut into two equal half or more and also pole strength remains same but magnetic moment reduces due to decrease in the length of the magnet. If a bar magnet is suspended by a thread, it will come to rest in a position close to the north-south direction. The end of the magnetic toward the north is called north pole (N-poled of the magnet and the other end the south pole (S-pole).
[12] A new technology which provides the ability to create an artificial world and have people interact with it is called –
A.
Televirtuality
B.
Virtual reality
C.
Alternate reality
D.
3-D reality
Ans:
Virtual reality
Explanation :
Virtual reality (VR) is a term that applies to computer-simulated environments that can simulate physical presence in places in the real world, as well as in imaginary worlds. Most current virtual reality environments are primarily visual experiences, displayed either on a computer screen or through special stereoscopic displays, but some simulations include additional sensory information, such as sound through speakers or headphones.
[13] A proton is identical to _.
A.
the nucleus of helium
B.
the nucleus of a hydrogen atom
C.
an alpha-particle
D.
a beta particle
Ans:
a beta particle
Explanation :
0
[14] What should a person on a freely rotating turn table do to decrease his (angular) speed?
A.
Bring his hands together
B.
Raise his hands up
C.
Spread his hands outwards
D.
Sit down with raised hands
Ans:
Spread his hands outwards
Explanation :
The answer is related to the conservation of angular momentum. The person on the rotating table will maintain approximately the same angular momentum during the spin. If he moves his arms in, it will reduce the rotational inertia by reducing the distance of the mass of her arms and hands from the axis of rotation.
[15] In a rechargeable cell what kind of energy is stored within the cell?
A.
Electrical energy
B.
Potential energy
C.
Chemical energy
D.
Kinetic energy
Ans:
Chemical energy
Explanation :
In electricity, a battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. A battery is a device that converts chemical energy directly to electrical energy. It consists of a number of voltaic cells; each voltaic cell consists of two half-cells connected in series by a conductive electrolyte containing anions and cations.
[16] Which one of the following lenses should be used to correct the defect of astigmatism?
A.
Cylindrical lens
B.
Concave lens
C.
Convex lens
D.
Bifocal lens
Ans:
Cylindrical lens
Explanation :
Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina. This may be due to an irregular or toric curvature of the cornea or lens. The two types of astigmatism are regular and irregular. Irregular astigmatism is often caused by a corneal scar or scattering in the crystalline lens, and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses.
[17] Danger signals are generally red as red light –
A.
is least bright
B.
undergoes least deviation
C.
has lowest velocity
D.
gives comfort to eye
Ans:
undergoes least deviation
Explanation :
The primary reason why the colour red is used for danger signals is that red light is scattered the least by air molecules. The effect of scattering is inversely related to the fourth power of the wavelength of a colour. Therefore blue which has the least wavelength of all the visible radiations is scattered the most and red which has the highest wavelength of all the colours we can see is scattered the least.
[18] A simple microscope consists of :
A.
a short focus convex lens
B.
a long focus convex lens
C.
a short focus concave lens
D.
a long focus concave lens
Ans:
a short focus convex lens
Explanation :
Simple microscope - light microscope consisting of a short focus single convex lens is used to produce an enlarged image. The magnifying glass was invented by Roger Bacon in 1250. In the original 'simple' microscopes, a single light path went through the object viewed and one lens, increasing the visibility of the object by some amount (magnification).
[19] A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to –
A.
Outward pull on him
B.
Inertia of motion
C.
Change in momentum
D.
Change in acceleration
Ans:
Inertia of motion
Explanation :
This is inertia of direction. It is the ability of body to be in a state of direction of motion for example sun holds planets in a fixed elliptical path this is one of the examples of inertia of direction. Inertia of direction is non-existent however inertia only apply to a body at rest or moving with a constant velocity. It is the property possessed by a body to resist change. In other way we can say that if a body moves in a particular direction under the action of a force and if the force is removed then the will continue to move in the same direction unless stopped under the action of another opposing force for a body at rest it under the inertia of rest whereas inertia of motion is for bodies in motion.
[20] When pressure is increased the melting point of ice –
A.
increases
B.
does not change
C.
decreases
D.
depends on the impurities in the ice
Ans:
decreases
Explanation :
In this case, if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point — allowing more solid to become liquid and hence when we increase pressure, the melting point of ice decreases because of the inversal relationship between the pressure and melting point of ice.
[21] What apparatus is used to locate a submerged object?
A.
Radar
B.
Sonar
C.
Quasar
D.
Pulsar
Ans:
Sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.
[22] The instrument which uses sound waves to measure the depth of oceans is –
A.
Radar
B.
Sonar
C.
Altimeter
D.
Venturimeter
Ans:
Sonar
Explanation :
The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations.
[23] One Kilowatt hour is equal to—
A.
3.6 Mega Joule
B.
3.8 Mega Joule
C.
3.2 Mega Joule
D.
4.0 Mega Joule
Ans:
3.6 Mega Joule
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
Copper: 9% less conductive than silver; aluminium is 10% less conductive than copper; while steel is the least conductive among the given options. The most electrically conductive metal is silver.
[6] At what temperature are the temperature on Celsius and Fahrenheit scales equal?
A.
273° Celsius
B.
-273° Celsius
C.
-40° Celsius
D.
40° Celsius
Ans:
-40° Celsius
Explanation :
If C is the temperature in Celsius and F is the temperature in Fahrenheit then, C F - 32 = S 9 They are equal at -40° (minus 40 degrees), because if we convert the readings of Celsius and Fahrenheit, we will have: Celsius to Fahrenheit (-40°C x 9/5) +32 = -72 + 32 = -40°F. Fahrenheit to Celsius (-40°F - 32°) x 5/9 = (-72) x 5/9 = -40°C.
[7] The electric charge is stored in a device called:
A.
Inductor
B.
Capacitor
C.
Resister
D.
Transformer
Ans:
Capacitor
Explanation :
A capacitor is a passive two-terminal electronic component that stores electrical energy in an electric field. The effect of a capacitor is known as capacitance.
[8] SI unit for the surface tension is .
A.
kg/m2
B.
kg/m3
C.
N/m
D.
kg/m
Ans:
N/m
Explanation :
Surface tension, represented by the symbol γ (alternatively σ or T), is measured in force per unit length. Its SI unit is newton per meter but the cgs unit of dyne per centimeter is also used.
[9] The density of the liquid when heated –
A.
decreases
B.
increases
C.
does not change
D.
may increase of decrease depending on pressure
Ans:
decreases
Explanation :
The mass density of a material varies with temperature and pressure. Increasing the temperature of a substance (with some exceptions) decreases its density by increasing the volume of that substance. In most materials, heating the bottom of a fluid results in convection of the heat from bottom to top of the fluid due to the decrease of the density of the heated fluid.
[10] The distance between node and adjacent antinodes is 30 cm. The wavelength is -
A.
30 cm.
B.
90 cm.
C.
120 cm.
D.
60 cm.
Ans:
60 cm.
Explanation :
A node is a point along a standing wave where the wave has minimal amplitude. The opposite of a node is an antinode, a point where the amplitude of the standing wave is a maximum.
[11] When a bar magnet is cut into two equal halves, the pole strength of each piece –
A.
becomes double
B.
becomes half
C.
becomes zero
D.
remains the same
Ans:
remains the same
Explanation :
The poles remains same whether the magnet is cut into two equal half or more and also pole strength remains same but magnetic moment reduces due to decrease in the length of the magnet. If a bar magnet is suspended by a thread, it will come to rest in a position close to the north-south direction. The end of the magnetic toward the north is called north pole (N-poled of the magnet and the other end the south pole (S-pole).
[12] A new technology which provides the ability to create an artificial world and have people interact with it is called –
A.
Televirtuality
B.
Virtual reality
C.
Alternate reality
D.
3-D reality
Ans:
Virtual reality
Explanation :
Virtual reality (VR) is a term that applies to computer-simulated environments that can simulate physical presence in places in the real world, as well as in imaginary worlds. Most current virtual reality environments are primarily visual experiences, displayed either on a computer screen or through special stereoscopic displays, but some simulations include additional sensory information, such as sound through speakers or headphones.
[13] A proton is identical to _.
A.
the nucleus of helium
B.
the nucleus of a hydrogen atom
C.
an alpha-particle
D.
a beta particle
Ans:
a beta particle
Explanation :
0
[14] What should a person on a freely rotating turn table do to decrease his (angular) speed?
A.
Bring his hands together
B.
Raise his hands up
C.
Spread his hands outwards
D.
Sit down with raised hands
Ans:
Spread his hands outwards
Explanation :
The answer is related to the conservation of angular momentum. The person on the rotating table will maintain approximately the same angular momentum during the spin. If he moves his arms in, it will reduce the rotational inertia by reducing the distance of the mass of her arms and hands from the axis of rotation.
[15] In a rechargeable cell what kind of energy is stored within the cell?
A.
Electrical energy
B.
Potential energy
C.
Chemical energy
D.
Kinetic energy
Ans:
Chemical energy
Explanation :
In electricity, a battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. A battery is a device that converts chemical energy directly to electrical energy. It consists of a number of voltaic cells; each voltaic cell consists of two half-cells connected in series by a conductive electrolyte containing anions and cations.
[16] Which one of the following lenses should be used to correct the defect of astigmatism?
A.
Cylindrical lens
B.
Concave lens
C.
Convex lens
D.
Bifocal lens
Ans:
Cylindrical lens
Explanation :
Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina. This may be due to an irregular or toric curvature of the cornea or lens. The two types of astigmatism are regular and irregular. Irregular astigmatism is often caused by a corneal scar or scattering in the crystalline lens, and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses.
[17] Danger signals are generally red as red light –
A.
is least bright
B.
undergoes least deviation
C.
has lowest velocity
D.
gives comfort to eye
Ans:
undergoes least deviation
Explanation :
The primary reason why the colour red is used for danger signals is that red light is scattered the least by air molecules. The effect of scattering is inversely related to the fourth power of the wavelength of a colour. Therefore blue which has the least wavelength of all the visible radiations is scattered the most and red which has the highest wavelength of all the colours we can see is scattered the least.
[18] A simple microscope consists of :
A.
a short focus convex lens
B.
a long focus convex lens
C.
a short focus concave lens
D.
a long focus concave lens
Ans:
a short focus convex lens
Explanation :
Simple microscope - light microscope consisting of a short focus single convex lens is used to produce an enlarged image. The magnifying glass was invented by Roger Bacon in 1250. In the original 'simple' microscopes, a single light path went through the object viewed and one lens, increasing the visibility of the object by some amount (magnification).
[19] A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to –
A.
Outward pull on him
B.
Inertia of motion
C.
Change in momentum
D.
Change in acceleration
Ans:
Inertia of motion
Explanation :
This is inertia of direction. It is the ability of body to be in a state of direction of motion for example sun holds planets in a fixed elliptical path this is one of the examples of inertia of direction. Inertia of direction is non-existent however inertia only apply to a body at rest or moving with a constant velocity. It is the property possessed by a body to resist change. In other way we can say that if a body moves in a particular direction under the action of a force and if the force is removed then the will continue to move in the same direction unless stopped under the action of another opposing force for a body at rest it under the inertia of rest whereas inertia of motion is for bodies in motion.
[20] When pressure is increased the melting point of ice –
A.
increases
B.
does not change
C.
decreases
D.
depends on the impurities in the ice
Ans:
decreases
Explanation :
In this case, if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point — allowing more solid to become liquid and hence when we increase pressure, the melting point of ice decreases because of the inversal relationship between the pressure and melting point of ice.
[21] What apparatus is used to locate a submerged object?
A.
Radar
B.
Sonar
C.
Quasar
D.
Pulsar
Ans:
Sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.
[22] The instrument which uses sound waves to measure the depth of oceans is –
A.
Radar
B.
Sonar
C.
Altimeter
D.
Venturimeter
Ans:
Sonar
Explanation :
The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations.
[23] One Kilowatt hour is equal to—
A.
3.6 Mega Joule
B.
3.8 Mega Joule
C.
3.2 Mega Joule
D.
4.0 Mega Joule
Ans:
3.6 Mega Joule
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
A capacitor is a passive two-terminal electronic component that stores electrical energy in an electric field. The effect of a capacitor is known as capacitance.
[8] SI unit for the surface tension is .
A.
kg/m2
B.
kg/m3
C.
N/m
D.
kg/m
Ans:
N/m
Explanation :
Surface tension, represented by the symbol γ (alternatively σ or T), is measured in force per unit length. Its SI unit is newton per meter but the cgs unit of dyne per centimeter is also used.
[9] The density of the liquid when heated –
A.
decreases
B.
increases
C.
does not change
D.
may increase of decrease depending on pressure
Ans:
decreases
Explanation :
The mass density of a material varies with temperature and pressure. Increasing the temperature of a substance (with some exceptions) decreases its density by increasing the volume of that substance. In most materials, heating the bottom of a fluid results in convection of the heat from bottom to top of the fluid due to the decrease of the density of the heated fluid.
[10] The distance between node and adjacent antinodes is 30 cm. The wavelength is -
A.
30 cm.
B.
90 cm.
C.
120 cm.
D.
60 cm.
Ans:
60 cm.
Explanation :
A node is a point along a standing wave where the wave has minimal amplitude. The opposite of a node is an antinode, a point where the amplitude of the standing wave is a maximum.
[11] When a bar magnet is cut into two equal halves, the pole strength of each piece –
A.
becomes double
B.
becomes half
C.
becomes zero
D.
remains the same
Ans:
remains the same
Explanation :
The poles remains same whether the magnet is cut into two equal half or more and also pole strength remains same but magnetic moment reduces due to decrease in the length of the magnet. If a bar magnet is suspended by a thread, it will come to rest in a position close to the north-south direction. The end of the magnetic toward the north is called north pole (N-poled of the magnet and the other end the south pole (S-pole).
[12] A new technology which provides the ability to create an artificial world and have people interact with it is called –
A.
Televirtuality
B.
Virtual reality
C.
Alternate reality
D.
3-D reality
Ans:
Virtual reality
Explanation :
Virtual reality (VR) is a term that applies to computer-simulated environments that can simulate physical presence in places in the real world, as well as in imaginary worlds. Most current virtual reality environments are primarily visual experiences, displayed either on a computer screen or through special stereoscopic displays, but some simulations include additional sensory information, such as sound through speakers or headphones.
[13] A proton is identical to _.
A.
the nucleus of helium
B.
the nucleus of a hydrogen atom
C.
an alpha-particle
D.
a beta particle
Ans:
a beta particle
Explanation :
0
[14] What should a person on a freely rotating turn table do to decrease his (angular) speed?
A.
Bring his hands together
B.
Raise his hands up
C.
Spread his hands outwards
D.
Sit down with raised hands
Ans:
Spread his hands outwards
Explanation :
The answer is related to the conservation of angular momentum. The person on the rotating table will maintain approximately the same angular momentum during the spin. If he moves his arms in, it will reduce the rotational inertia by reducing the distance of the mass of her arms and hands from the axis of rotation.
[15] In a rechargeable cell what kind of energy is stored within the cell?
A.
Electrical energy
B.
Potential energy
C.
Chemical energy
D.
Kinetic energy
Ans:
Chemical energy
Explanation :
In electricity, a battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. A battery is a device that converts chemical energy directly to electrical energy. It consists of a number of voltaic cells; each voltaic cell consists of two half-cells connected in series by a conductive electrolyte containing anions and cations.
[16] Which one of the following lenses should be used to correct the defect of astigmatism?
A.
Cylindrical lens
B.
Concave lens
C.
Convex lens
D.
Bifocal lens
Ans:
Cylindrical lens
Explanation :
Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina. This may be due to an irregular or toric curvature of the cornea or lens. The two types of astigmatism are regular and irregular. Irregular astigmatism is often caused by a corneal scar or scattering in the crystalline lens, and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses.
[17] Danger signals are generally red as red light –
A.
is least bright
B.
undergoes least deviation
C.
has lowest velocity
D.
gives comfort to eye
Ans:
undergoes least deviation
Explanation :
The primary reason why the colour red is used for danger signals is that red light is scattered the least by air molecules. The effect of scattering is inversely related to the fourth power of the wavelength of a colour. Therefore blue which has the least wavelength of all the visible radiations is scattered the most and red which has the highest wavelength of all the colours we can see is scattered the least.
[18] A simple microscope consists of :
A.
a short focus convex lens
B.
a long focus convex lens
C.
a short focus concave lens
D.
a long focus concave lens
Ans:
a short focus convex lens
Explanation :
Simple microscope - light microscope consisting of a short focus single convex lens is used to produce an enlarged image. The magnifying glass was invented by Roger Bacon in 1250. In the original 'simple' microscopes, a single light path went through the object viewed and one lens, increasing the visibility of the object by some amount (magnification).
[19] A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to –
A.
Outward pull on him
B.
Inertia of motion
C.
Change in momentum
D.
Change in acceleration
Ans:
Inertia of motion
Explanation :
This is inertia of direction. It is the ability of body to be in a state of direction of motion for example sun holds planets in a fixed elliptical path this is one of the examples of inertia of direction. Inertia of direction is non-existent however inertia only apply to a body at rest or moving with a constant velocity. It is the property possessed by a body to resist change. In other way we can say that if a body moves in a particular direction under the action of a force and if the force is removed then the will continue to move in the same direction unless stopped under the action of another opposing force for a body at rest it under the inertia of rest whereas inertia of motion is for bodies in motion.
[20] When pressure is increased the melting point of ice –
A.
increases
B.
does not change
C.
decreases
D.
depends on the impurities in the ice
Ans:
decreases
Explanation :
In this case, if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point — allowing more solid to become liquid and hence when we increase pressure, the melting point of ice decreases because of the inversal relationship between the pressure and melting point of ice.
[21] What apparatus is used to locate a submerged object?
A.
Radar
B.
Sonar
C.
Quasar
D.
Pulsar
Ans:
Sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.
[22] The instrument which uses sound waves to measure the depth of oceans is –
A.
Radar
B.
Sonar
C.
Altimeter
D.
Venturimeter
Ans:
Sonar
Explanation :
The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations.
[23] One Kilowatt hour is equal to—
A.
3.6 Mega Joule
B.
3.8 Mega Joule
C.
3.2 Mega Joule
D.
4.0 Mega Joule
Ans:
3.6 Mega Joule
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
The mass density of a material varies with temperature and pressure. Increasing the temperature of a substance (with some exceptions) decreases its density by increasing the volume of that substance. In most materials, heating the bottom of a fluid results in convection of the heat from bottom to top of the fluid due to the decrease of the density of the heated fluid.
[10] The distance between node and adjacent antinodes is 30 cm. The wavelength is -
A.
30 cm.
B.
90 cm.
C.
120 cm.
D.
60 cm.
Ans:
60 cm.
Explanation :
A node is a point along a standing wave where the wave has minimal amplitude. The opposite of a node is an antinode, a point where the amplitude of the standing wave is a maximum.
[11] When a bar magnet is cut into two equal halves, the pole strength of each piece –
A.
becomes double
B.
becomes half
C.
becomes zero
D.
remains the same
Ans:
remains the same
Explanation :
The poles remains same whether the magnet is cut into two equal half or more and also pole strength remains same but magnetic moment reduces due to decrease in the length of the magnet. If a bar magnet is suspended by a thread, it will come to rest in a position close to the north-south direction. The end of the magnetic toward the north is called north pole (N-poled of the magnet and the other end the south pole (S-pole).
[12] A new technology which provides the ability to create an artificial world and have people interact with it is called –
A.
Televirtuality
B.
Virtual reality
C.
Alternate reality
D.
3-D reality
Ans:
Virtual reality
Explanation :
Virtual reality (VR) is a term that applies to computer-simulated environments that can simulate physical presence in places in the real world, as well as in imaginary worlds. Most current virtual reality environments are primarily visual experiences, displayed either on a computer screen or through special stereoscopic displays, but some simulations include additional sensory information, such as sound through speakers or headphones.
[13] A proton is identical to _.
A.
the nucleus of helium
B.
the nucleus of a hydrogen atom
C.
an alpha-particle
D.
a beta particle
Ans:
a beta particle
Explanation :
0
[14] What should a person on a freely rotating turn table do to decrease his (angular) speed?
A.
Bring his hands together
B.
Raise his hands up
C.
Spread his hands outwards
D.
Sit down with raised hands
Ans:
Spread his hands outwards
Explanation :
The answer is related to the conservation of angular momentum. The person on the rotating table will maintain approximately the same angular momentum during the spin. If he moves his arms in, it will reduce the rotational inertia by reducing the distance of the mass of her arms and hands from the axis of rotation.
[15] In a rechargeable cell what kind of energy is stored within the cell?
A.
Electrical energy
B.
Potential energy
C.
Chemical energy
D.
Kinetic energy
Ans:
Chemical energy
Explanation :
In electricity, a battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. A battery is a device that converts chemical energy directly to electrical energy. It consists of a number of voltaic cells; each voltaic cell consists of two half-cells connected in series by a conductive electrolyte containing anions and cations.
[16] Which one of the following lenses should be used to correct the defect of astigmatism?
A.
Cylindrical lens
B.
Concave lens
C.
Convex lens
D.
Bifocal lens
Ans:
Cylindrical lens
Explanation :
Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina. This may be due to an irregular or toric curvature of the cornea or lens. The two types of astigmatism are regular and irregular. Irregular astigmatism is often caused by a corneal scar or scattering in the crystalline lens, and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses.
[17] Danger signals are generally red as red light –
A.
is least bright
B.
undergoes least deviation
C.
has lowest velocity
D.
gives comfort to eye
Ans:
undergoes least deviation
Explanation :
The primary reason why the colour red is used for danger signals is that red light is scattered the least by air molecules. The effect of scattering is inversely related to the fourth power of the wavelength of a colour. Therefore blue which has the least wavelength of all the visible radiations is scattered the most and red which has the highest wavelength of all the colours we can see is scattered the least.
[18] A simple microscope consists of :
A.
a short focus convex lens
B.
a long focus convex lens
C.
a short focus concave lens
D.
a long focus concave lens
Ans:
a short focus convex lens
Explanation :
Simple microscope - light microscope consisting of a short focus single convex lens is used to produce an enlarged image. The magnifying glass was invented by Roger Bacon in 1250. In the original 'simple' microscopes, a single light path went through the object viewed and one lens, increasing the visibility of the object by some amount (magnification).
[19] A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to –
A.
Outward pull on him
B.
Inertia of motion
C.
Change in momentum
D.
Change in acceleration
Ans:
Inertia of motion
Explanation :
This is inertia of direction. It is the ability of body to be in a state of direction of motion for example sun holds planets in a fixed elliptical path this is one of the examples of inertia of direction. Inertia of direction is non-existent however inertia only apply to a body at rest or moving with a constant velocity. It is the property possessed by a body to resist change. In other way we can say that if a body moves in a particular direction under the action of a force and if the force is removed then the will continue to move in the same direction unless stopped under the action of another opposing force for a body at rest it under the inertia of rest whereas inertia of motion is for bodies in motion.
[20] When pressure is increased the melting point of ice –
A.
increases
B.
does not change
C.
decreases
D.
depends on the impurities in the ice
Ans:
decreases
Explanation :
In this case, if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point — allowing more solid to become liquid and hence when we increase pressure, the melting point of ice decreases because of the inversal relationship between the pressure and melting point of ice.
[21] What apparatus is used to locate a submerged object?
A.
Radar
B.
Sonar
C.
Quasar
D.
Pulsar
Ans:
Sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.
[22] The instrument which uses sound waves to measure the depth of oceans is –
A.
Radar
B.
Sonar
C.
Altimeter
D.
Venturimeter
Ans:
Sonar
Explanation :
The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations.
[23] One Kilowatt hour is equal to—
A.
3.6 Mega Joule
B.
3.8 Mega Joule
C.
3.2 Mega Joule
D.
4.0 Mega Joule
Ans:
3.6 Mega Joule
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
The poles remains same whether the magnet is cut into two equal half or more and also pole strength remains same but magnetic moment reduces due to decrease in the length of the magnet. If a bar magnet is suspended by a thread, it will come to rest in a position close to the north-south direction. The end of the magnetic toward the north is called north pole (N-poled of the magnet and the other end the south pole (S-pole).
[12] A new technology which provides the ability to create an artificial world and have people interact with it is called –
A.
Televirtuality
B.
Virtual reality
C.
Alternate reality
D.
3-D reality
Ans:
Virtual reality
Explanation :
Virtual reality (VR) is a term that applies to computer-simulated environments that can simulate physical presence in places in the real world, as well as in imaginary worlds. Most current virtual reality environments are primarily visual experiences, displayed either on a computer screen or through special stereoscopic displays, but some simulations include additional sensory information, such as sound through speakers or headphones.
[13] A proton is identical to _.
A.
the nucleus of helium
B.
the nucleus of a hydrogen atom
C.
an alpha-particle
D.
a beta particle
Ans:
a beta particle
Explanation :
0
[14] What should a person on a freely rotating turn table do to decrease his (angular) speed?
A.
Bring his hands together
B.
Raise his hands up
C.
Spread his hands outwards
D.
Sit down with raised hands
Ans:
Spread his hands outwards
Explanation :
The answer is related to the conservation of angular momentum. The person on the rotating table will maintain approximately the same angular momentum during the spin. If he moves his arms in, it will reduce the rotational inertia by reducing the distance of the mass of her arms and hands from the axis of rotation.
[15] In a rechargeable cell what kind of energy is stored within the cell?
A.
Electrical energy
B.
Potential energy
C.
Chemical energy
D.
Kinetic energy
Ans:
Chemical energy
Explanation :
In electricity, a battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. A battery is a device that converts chemical energy directly to electrical energy. It consists of a number of voltaic cells; each voltaic cell consists of two half-cells connected in series by a conductive electrolyte containing anions and cations.
[16] Which one of the following lenses should be used to correct the defect of astigmatism?
A.
Cylindrical lens
B.
Concave lens
C.
Convex lens
D.
Bifocal lens
Ans:
Cylindrical lens
Explanation :
Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina. This may be due to an irregular or toric curvature of the cornea or lens. The two types of astigmatism are regular and irregular. Irregular astigmatism is often caused by a corneal scar or scattering in the crystalline lens, and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses.
[17] Danger signals are generally red as red light –
A.
is least bright
B.
undergoes least deviation
C.
has lowest velocity
D.
gives comfort to eye
Ans:
undergoes least deviation
Explanation :
The primary reason why the colour red is used for danger signals is that red light is scattered the least by air molecules. The effect of scattering is inversely related to the fourth power of the wavelength of a colour. Therefore blue which has the least wavelength of all the visible radiations is scattered the most and red which has the highest wavelength of all the colours we can see is scattered the least.
[18] A simple microscope consists of :
A.
a short focus convex lens
B.
a long focus convex lens
C.
a short focus concave lens
D.
a long focus concave lens
Ans:
a short focus convex lens
Explanation :
Simple microscope - light microscope consisting of a short focus single convex lens is used to produce an enlarged image. The magnifying glass was invented by Roger Bacon in 1250. In the original 'simple' microscopes, a single light path went through the object viewed and one lens, increasing the visibility of the object by some amount (magnification).
[19] A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to –
A.
Outward pull on him
B.
Inertia of motion
C.
Change in momentum
D.
Change in acceleration
Ans:
Inertia of motion
Explanation :
This is inertia of direction. It is the ability of body to be in a state of direction of motion for example sun holds planets in a fixed elliptical path this is one of the examples of inertia of direction. Inertia of direction is non-existent however inertia only apply to a body at rest or moving with a constant velocity. It is the property possessed by a body to resist change. In other way we can say that if a body moves in a particular direction under the action of a force and if the force is removed then the will continue to move in the same direction unless stopped under the action of another opposing force for a body at rest it under the inertia of rest whereas inertia of motion is for bodies in motion.
[20] When pressure is increased the melting point of ice –
A.
increases
B.
does not change
C.
decreases
D.
depends on the impurities in the ice
Ans:
decreases
Explanation :
In this case, if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point — allowing more solid to become liquid and hence when we increase pressure, the melting point of ice decreases because of the inversal relationship between the pressure and melting point of ice.
[21] What apparatus is used to locate a submerged object?
A.
Radar
B.
Sonar
C.
Quasar
D.
Pulsar
Ans:
Sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.
[22] The instrument which uses sound waves to measure the depth of oceans is –
A.
Radar
B.
Sonar
C.
Altimeter
D.
Venturimeter
Ans:
Sonar
Explanation :
The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations.
[23] One Kilowatt hour is equal to—
A.
3.6 Mega Joule
B.
3.8 Mega Joule
C.
3.2 Mega Joule
D.
4.0 Mega Joule
Ans:
3.6 Mega Joule
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
0
[14] What should a person on a freely rotating turn table do to decrease his (angular) speed?
A.
Bring his hands together
B.
Raise his hands up
C.
Spread his hands outwards
D.
Sit down with raised hands
Ans:
Spread his hands outwards
Explanation :
The answer is related to the conservation of angular momentum. The person on the rotating table will maintain approximately the same angular momentum during the spin. If he moves his arms in, it will reduce the rotational inertia by reducing the distance of the mass of her arms and hands from the axis of rotation.
[15] In a rechargeable cell what kind of energy is stored within the cell?
A.
Electrical energy
B.
Potential energy
C.
Chemical energy
D.
Kinetic energy
Ans:
Chemical energy
Explanation :
In electricity, a battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. A battery is a device that converts chemical energy directly to electrical energy. It consists of a number of voltaic cells; each voltaic cell consists of two half-cells connected in series by a conductive electrolyte containing anions and cations.
[16] Which one of the following lenses should be used to correct the defect of astigmatism?
A.
Cylindrical lens
B.
Concave lens
C.
Convex lens
D.
Bifocal lens
Ans:
Cylindrical lens
Explanation :
Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina. This may be due to an irregular or toric curvature of the cornea or lens. The two types of astigmatism are regular and irregular. Irregular astigmatism is often caused by a corneal scar or scattering in the crystalline lens, and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses.
[17] Danger signals are generally red as red light –
A.
is least bright
B.
undergoes least deviation
C.
has lowest velocity
D.
gives comfort to eye
Ans:
undergoes least deviation
Explanation :
The primary reason why the colour red is used for danger signals is that red light is scattered the least by air molecules. The effect of scattering is inversely related to the fourth power of the wavelength of a colour. Therefore blue which has the least wavelength of all the visible radiations is scattered the most and red which has the highest wavelength of all the colours we can see is scattered the least.
[18] A simple microscope consists of :
A.
a short focus convex lens
B.
a long focus convex lens
C.
a short focus concave lens
D.
a long focus concave lens
Ans:
a short focus convex lens
Explanation :
Simple microscope - light microscope consisting of a short focus single convex lens is used to produce an enlarged image. The magnifying glass was invented by Roger Bacon in 1250. In the original 'simple' microscopes, a single light path went through the object viewed and one lens, increasing the visibility of the object by some amount (magnification).
[19] A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to –
A.
Outward pull on him
B.
Inertia of motion
C.
Change in momentum
D.
Change in acceleration
Ans:
Inertia of motion
Explanation :
This is inertia of direction. It is the ability of body to be in a state of direction of motion for example sun holds planets in a fixed elliptical path this is one of the examples of inertia of direction. Inertia of direction is non-existent however inertia only apply to a body at rest or moving with a constant velocity. It is the property possessed by a body to resist change. In other way we can say that if a body moves in a particular direction under the action of a force and if the force is removed then the will continue to move in the same direction unless stopped under the action of another opposing force for a body at rest it under the inertia of rest whereas inertia of motion is for bodies in motion.
[20] When pressure is increased the melting point of ice –
A.
increases
B.
does not change
C.
decreases
D.
depends on the impurities in the ice
Ans:
decreases
Explanation :
In this case, if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point — allowing more solid to become liquid and hence when we increase pressure, the melting point of ice decreases because of the inversal relationship between the pressure and melting point of ice.
[21] What apparatus is used to locate a submerged object?
A.
Radar
B.
Sonar
C.
Quasar
D.
Pulsar
Ans:
Sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.
[22] The instrument which uses sound waves to measure the depth of oceans is –
A.
Radar
B.
Sonar
C.
Altimeter
D.
Venturimeter
Ans:
Sonar
Explanation :
The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations.
[23] One Kilowatt hour is equal to—
A.
3.6 Mega Joule
B.
3.8 Mega Joule
C.
3.2 Mega Joule
D.
4.0 Mega Joule
Ans:
3.6 Mega Joule
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
In electricity, a battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. A battery is a device that converts chemical energy directly to electrical energy. It consists of a number of voltaic cells; each voltaic cell consists of two half-cells connected in series by a conductive electrolyte containing anions and cations.
[16] Which one of the following lenses should be used to correct the defect of astigmatism?
A.
Cylindrical lens
B.
Concave lens
C.
Convex lens
D.
Bifocal lens
Ans:
Cylindrical lens
Explanation :
Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina. This may be due to an irregular or toric curvature of the cornea or lens. The two types of astigmatism are regular and irregular. Irregular astigmatism is often caused by a corneal scar or scattering in the crystalline lens, and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses.
[17] Danger signals are generally red as red light –
A.
is least bright
B.
undergoes least deviation
C.
has lowest velocity
D.
gives comfort to eye
Ans:
undergoes least deviation
Explanation :
The primary reason why the colour red is used for danger signals is that red light is scattered the least by air molecules. The effect of scattering is inversely related to the fourth power of the wavelength of a colour. Therefore blue which has the least wavelength of all the visible radiations is scattered the most and red which has the highest wavelength of all the colours we can see is scattered the least.
[18] A simple microscope consists of :
A.
a short focus convex lens
B.
a long focus convex lens
C.
a short focus concave lens
D.
a long focus concave lens
Ans:
a short focus convex lens
Explanation :
Simple microscope - light microscope consisting of a short focus single convex lens is used to produce an enlarged image. The magnifying glass was invented by Roger Bacon in 1250. In the original 'simple' microscopes, a single light path went through the object viewed and one lens, increasing the visibility of the object by some amount (magnification).
[19] A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to –
A.
Outward pull on him
B.
Inertia of motion
C.
Change in momentum
D.
Change in acceleration
Ans:
Inertia of motion
Explanation :
This is inertia of direction. It is the ability of body to be in a state of direction of motion for example sun holds planets in a fixed elliptical path this is one of the examples of inertia of direction. Inertia of direction is non-existent however inertia only apply to a body at rest or moving with a constant velocity. It is the property possessed by a body to resist change. In other way we can say that if a body moves in a particular direction under the action of a force and if the force is removed then the will continue to move in the same direction unless stopped under the action of another opposing force for a body at rest it under the inertia of rest whereas inertia of motion is for bodies in motion.
[20] When pressure is increased the melting point of ice –
A.
increases
B.
does not change
C.
decreases
D.
depends on the impurities in the ice
Ans:
decreases
Explanation :
In this case, if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point — allowing more solid to become liquid and hence when we increase pressure, the melting point of ice decreases because of the inversal relationship between the pressure and melting point of ice.
[21] What apparatus is used to locate a submerged object?
A.
Radar
B.
Sonar
C.
Quasar
D.
Pulsar
Ans:
Sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.
[22] The instrument which uses sound waves to measure the depth of oceans is –
A.
Radar
B.
Sonar
C.
Altimeter
D.
Venturimeter
Ans:
Sonar
Explanation :
The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations.
[23] One Kilowatt hour is equal to—
A.
3.6 Mega Joule
B.
3.8 Mega Joule
C.
3.2 Mega Joule
D.
4.0 Mega Joule
Ans:
3.6 Mega Joule
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
The primary reason why the colour red is used for danger signals is that red light is scattered the least by air molecules. The effect of scattering is inversely related to the fourth power of the wavelength of a colour. Therefore blue which has the least wavelength of all the visible radiations is scattered the most and red which has the highest wavelength of all the colours we can see is scattered the least.
[18] A simple microscope consists of :
A.
a short focus convex lens
B.
a long focus convex lens
C.
a short focus concave lens
D.
a long focus concave lens
Ans:
a short focus convex lens
Explanation :
Simple microscope - light microscope consisting of a short focus single convex lens is used to produce an enlarged image. The magnifying glass was invented by Roger Bacon in 1250. In the original 'simple' microscopes, a single light path went through the object viewed and one lens, increasing the visibility of the object by some amount (magnification).
[19] A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to –
A.
Outward pull on him
B.
Inertia of motion
C.
Change in momentum
D.
Change in acceleration
Ans:
Inertia of motion
Explanation :
This is inertia of direction. It is the ability of body to be in a state of direction of motion for example sun holds planets in a fixed elliptical path this is one of the examples of inertia of direction. Inertia of direction is non-existent however inertia only apply to a body at rest or moving with a constant velocity. It is the property possessed by a body to resist change. In other way we can say that if a body moves in a particular direction under the action of a force and if the force is removed then the will continue to move in the same direction unless stopped under the action of another opposing force for a body at rest it under the inertia of rest whereas inertia of motion is for bodies in motion.
[20] When pressure is increased the melting point of ice –
A.
increases
B.
does not change
C.
decreases
D.
depends on the impurities in the ice
Ans:
decreases
Explanation :
In this case, if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point — allowing more solid to become liquid and hence when we increase pressure, the melting point of ice decreases because of the inversal relationship between the pressure and melting point of ice.
[21] What apparatus is used to locate a submerged object?
A.
Radar
B.
Sonar
C.
Quasar
D.
Pulsar
Ans:
Sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.
[22] The instrument which uses sound waves to measure the depth of oceans is –
A.
Radar
B.
Sonar
C.
Altimeter
D.
Venturimeter
Ans:
Sonar
Explanation :
The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations.
[23] One Kilowatt hour is equal to—
A.
3.6 Mega Joule
B.
3.8 Mega Joule
C.
3.2 Mega Joule
D.
4.0 Mega Joule
Ans:
3.6 Mega Joule
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
This is inertia of direction. It is the ability of body to be in a state of direction of motion for example sun holds planets in a fixed elliptical path this is one of the examples of inertia of direction. Inertia of direction is non-existent however inertia only apply to a body at rest or moving with a constant velocity. It is the property possessed by a body to resist change. In other way we can say that if a body moves in a particular direction under the action of a force and if the force is removed then the will continue to move in the same direction unless stopped under the action of another opposing force for a body at rest it under the inertia of rest whereas inertia of motion is for bodies in motion.
[20] When pressure is increased the melting point of ice –
A.
increases
B.
does not change
C.
decreases
D.
depends on the impurities in the ice
Ans:
decreases
Explanation :
In this case, if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point — allowing more solid to become liquid and hence when we increase pressure, the melting point of ice decreases because of the inversal relationship between the pressure and melting point of ice.
[21] What apparatus is used to locate a submerged object?
A.
Radar
B.
Sonar
C.
Quasar
D.
Pulsar
Ans:
Sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.
[22] The instrument which uses sound waves to measure the depth of oceans is –
A.
Radar
B.
Sonar
C.
Altimeter
D.
Venturimeter
Ans:
Sonar
Explanation :
The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations.
[23] One Kilowatt hour is equal to—
A.
3.6 Mega Joule
B.
3.8 Mega Joule
C.
3.2 Mega Joule
D.
4.0 Mega Joule
Ans:
3.6 Mega Joule
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.
[22] The instrument which uses sound waves to measure the depth of oceans is –
A.
Radar
B.
Sonar
C.
Altimeter
D.
Venturimeter
Ans:
Sonar
Explanation :
The instrument which uses sound waves to measure the depth of oceans is sonar. Sound waves can travel much faster from one point to another. Sound waves are far more accurate for measuring these vast distances. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations.
[23] One Kilowatt hour is equal to—
A.
3.6 Mega Joule
B.
3.8 Mega Joule
C.
3.2 Mega Joule
D.
4.0 Mega Joule
Ans:
3.6 Mega Joule
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
The energy 1 kilowatt-hour (kWh) is 3600000 joules or 3.6 mega joule. In physics, energy is an indirectly observed quantity that is often understood as the ability of a physical system to do work on other physical systems. However, this must be understood as an overly simplified definition, as the laws of thermodynamics demonstrate that not all energy can perform work.
[24] Longitudinal waves cannot travel through –
A.
Vacuum
B.
Solid
C.
Liquid
D.
Gas
Ans:
Vacuum
Explanation :
Longitudinal waves cannot travel through vacuum because such wave requires a medium such as solid liquid or air to travel through. They cannot travel through vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave. Mechanical longitudinal waves are also called compressional waves or compression waves. Longitudinal waves include sound waves (vibrations in pressure, particle displacement, and particle velocity propagated in an elastic medium) and seismic P-waves (created by earthquakes and explosions).
[25] Electrostatic precipitator is used to control the pollution of –
A.
air
B.
water
C.
noise
D.
thermal
Ans:
air
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).
Explanation :
An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. In contrast to wet scrubbers which apply energy directly to the flowing fluid medium, an ESP applies energy only to the particulate matter being collected and therefore is very efficient in its consumption of energy (in the form of electricity).