[1] When water freezes its density –
A.
Decreases
B.
Becomes Zero
C.
Remains constant
D.
Increases
Ans:
Decreases
Explanation :
Water at ordinary temperatures contracts and increases in density as it is cooled, like most substances. But at about 4°C it reaches a maximum density and then decreases in density as it approaches the freezing point. This is referred to as anomalous property of water.
[2] Which of the following is the unit of perceived loudness of sound?
A.
Decibel
B.
Sone
C.
Hertz
D.
Phon
Ans:
Sone
Explanation :
Loudness is a subjective characteristic of a sound (as opposed to the sound-pressure level in decibels, which is objective and directly measurable). Perceived loudness of sound is a psycho-acoustic quantity that depends on sound pressure level, the frequency spectrum, and the time behavior of the sound in question.
[3] The element required for Solar energy conversion -
A.
Beryllium
B.
Silicon
C.
Tantalum
D.
Ultra pure carbon
Ans:
Silicon
Explanation :
Energy conversion. n. (General Physics) is the process of changing one form of energy into another, such as nuclear energy into heat or solar energy into electrical energy.
[4] The washing machine works on the principle of –
A.
Dialysis
B.
Diffusion
C.
Reverse osmosis
D.
Centrifugation
Ans:
Centrifugation
Explanation :
Washing machines work on the principle of centrifugation. They are based on medium sized centrifuges that put an object in rotation around a fixed axis, applying force perpendicular to the axis.
[5] The 'Choke' used with a tube light is basically –
A.
an inductor
B.
a capacitor
C.
a transformer
D.
a resistor
Ans:
an inductor
Explanation :
In electronics, a choke is an inductor used to block higher-frequency alternating current (AC) in an electrical circuit, while passing lower-frequency or direct current (DC). In a tubelight, the high voltage is created by suddenly interrupting the current in choke, which is connected in series with the tubelight.
[6] The temperature of a liquid is 32° F. What is its temperature in Celsius scale?
A.
32° C
B.
0° C
C.
100° C
D.
212° C
Ans:
0° C
Explanation :
The formulas for converting between degree Celsius and degree Fahrenheit are: °F = °C 9/5 + 32 and °C = (°F - 32) 5/9. So in Celsius scale, 32o F= 0° C
[7] Which of the following phenomenon helps to conclude that light is a transverse wave?
A.
interference
B.
diffraction
C.
polarization
D.
refraction
Ans:
polarization
Explanation :
The phenomena of interference and diffraction of light were successful beyond doubt to prove that light is a form of wave. But they failed to decide whether light is transverse or longitudinal wave. The fact that light is a transverse wave was established only after the discovery of the phenomenon of polarization.
[8] Plank's constant has the dimensions of :
A.
energy
B.
linear momentum
C.
angular momentum
D.
force
Ans:
energy
Explanation :
The Planck's constant (h) can be defined as a pro-portionality constant that relates the energy (E) of a photon to the frequency (?) of its associated electro-magnetic wave. Mathematically, Planck's Constant (h) = Energy (E)/frequency (?). The Planck constant is named after Max Planck, the instigator of quantum theory, who discovered it in 1900.
[9] When number of turns in a coil is tripled, without any change in the length of coil, its self inductance becomes?
A.
Nine times
B.
Three times
C.
Six times
D.
One-third
Ans:
Nine times
Explanation :
0
[10] The abbreviation LHC stands for which machine?
A.
Light Heat Collider
B.
Large Hadron Collider
C.
Long Heavy Collider
D.
Large High Collider
Ans:
Large Hadron Collider
Explanation :
LHC stands for Large Hadron Collider is the world's largest and most powerful particle collider that allows scientists to further test the properties of the Higgs boson. It lies in a tunnel beneath the France- Switzerland border near Geneva, Switzerland.
[11] Which of the following have the same unit?
A.
Work and power
B.
Torque and moment of inertia
C.
Work and torque
D.
Torque and angular momentum
Ans:
Work and torque
Explanation :
The SI unit of work is the Newton-metre or joule (J). A Newton meter is also the SI unit of torque (also called "moment" or "moment of force").
[12] In a particular system, the units of length, mass and time are chosen to be 10 cm, 10 g and 0.1 s respectively. The unit of force in this system will be equivalent to –
A.
0.1 N
B.
1 N
C.
10 N
D.
100 N
Ans:
0.1 N
Explanation :
0
[13] Relative humidity is expressed as –
A.
Grams
B.
Kilograms
C.
Percentage
D.
Ratio
Ans:
Percentage
Explanation :
Relative humidity is the amount of moisture in the air compared to what the air can "hold" at that temperature. It signifies the mass of water vapour present in the air expressed as a percentage of the mass that would be present in an equal volume of saturated air at the same temperature.
[14] Why is weightlessness experienced while orbiting the earth in space ships?
A.
Inertia
B.
Acceleration
C.
Zero gravity
D.
None of these
Ans:
None of these
Explanation :
The reason astronauts experience weightlessness which orbiting the earth in spaceships is that they are in free fall. A spacecraft in orbit is falling towards the Earth, because of gravity, but it is moving forward in its orbit fast enough that the path it follows is a curve that is a closed ellipse.
[15] Where is a transistor most likely to be found?
A.
Wrist watch
B.
Fuse
C.
Hearing aid
D.
Fluorescent lamp
Ans:
Hearing aid
Explanation :
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. The transistor invented in 1948 was well suited to the hearing aid application due to low power and small size; hearing aids were an early adopter of transistors. Transistors replaced the need for batteries in hearing aids
[16] What is the SI unit of electric current?
A.
Amperes
B.
Coulombs
C.
Joules
D.
Watts
Ans:
Amperes
Explanation :
The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second.
[17] An object is in static equilibrium when it is .
A.
at rest
B.
moving in a circular path
C.
moving with uniform velocity
D.
accelerating at high speed
Ans:
at rest
Explanation :
When forces acting on an object which is at rest are balanced, the object is said to be in a state of static equilibrium. The resultant of these forces equals zero.
[18] Equal volumes of different gases at any definite temperature and pressure have-
A.
Equal weights
B.
equal masses
C.
equal density
D.
equal no. of molecules
Ans:
equal no. of molecules
Explanation :
At equal volume of different gases at any definite temperature and pressure have equal no. of particles.
[19] Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings"?
A.
Doppler's Effect
B.
Newton's law of cooling
C.
Kirchhoff's Law
D.
Stefan's Law
Ans:
Newton's law of cooling
Explanation :
Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature.
[20] Which of the following reaction is the main cause of energy radiated from Sun?
A.
Nuclear fission
B.
Nuclear fusion
C.
Chemical reaction
D.
Diffusion reaction
Ans:
Nuclear fusion
Explanation :
The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.
[21] Every hot object emits –
A.
X-rays
B.
Visible light
C.
Infrared rays
D.
Ultraviolet rays
Ans:
Infrared rays
Explanation :
As per Planck's law, all objects emit electromagnetic radiation according to their temperature. Colder objects emit waves with very low frequency (such, as radio or microwaves), while hot objects emit infra- red rays or even ultraviolet and higher frequencies. At room temperature, most of the radiation is in the infra-red region.
[22] Postage Meter was invented by -
A.
Fyodor Pirotsky
B.
Arthur Pitney
C.
Fritz Pfleumer
D.
Stephen Perry
Ans:
Arthur Pitney
Explanation :
The first postal meter to be commercially produced and distributed was invented by Arthur Pitney. World's first postage meter on December 9, 1901.
[23] A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
A.
increase
B.
decrease
C.
remain unaffected
D.
have its shape changed
Ans:
increase
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
Water at ordinary temperatures contracts and increases in density as it is cooled, like most substances. But at about 4°C it reaches a maximum density and then decreases in density as it approaches the freezing point. This is referred to as anomalous property of water.
[2] Which of the following is the unit of perceived loudness of sound?
A.
Decibel
B.
Sone
C.
Hertz
D.
Phon
Ans:
Sone
Explanation :
Loudness is a subjective characteristic of a sound (as opposed to the sound-pressure level in decibels, which is objective and directly measurable). Perceived loudness of sound is a psycho-acoustic quantity that depends on sound pressure level, the frequency spectrum, and the time behavior of the sound in question.
[3] The element required for Solar energy conversion -
A.
Beryllium
B.
Silicon
C.
Tantalum
D.
Ultra pure carbon
Ans:
Silicon
Explanation :
Energy conversion. n. (General Physics) is the process of changing one form of energy into another, such as nuclear energy into heat or solar energy into electrical energy.
[4] The washing machine works on the principle of –
A.
Dialysis
B.
Diffusion
C.
Reverse osmosis
D.
Centrifugation
Ans:
Centrifugation
Explanation :
Washing machines work on the principle of centrifugation. They are based on medium sized centrifuges that put an object in rotation around a fixed axis, applying force perpendicular to the axis.
[5] The 'Choke' used with a tube light is basically –
A.
an inductor
B.
a capacitor
C.
a transformer
D.
a resistor
Ans:
an inductor
Explanation :
In electronics, a choke is an inductor used to block higher-frequency alternating current (AC) in an electrical circuit, while passing lower-frequency or direct current (DC). In a tubelight, the high voltage is created by suddenly interrupting the current in choke, which is connected in series with the tubelight.
[6] The temperature of a liquid is 32° F. What is its temperature in Celsius scale?
A.
32° C
B.
0° C
C.
100° C
D.
212° C
Ans:
0° C
Explanation :
The formulas for converting between degree Celsius and degree Fahrenheit are: °F = °C 9/5 + 32 and °C = (°F - 32) 5/9. So in Celsius scale, 32o F= 0° C
[7] Which of the following phenomenon helps to conclude that light is a transverse wave?
A.
interference
B.
diffraction
C.
polarization
D.
refraction
Ans:
polarization
Explanation :
The phenomena of interference and diffraction of light were successful beyond doubt to prove that light is a form of wave. But they failed to decide whether light is transverse or longitudinal wave. The fact that light is a transverse wave was established only after the discovery of the phenomenon of polarization.
[8] Plank's constant has the dimensions of :
A.
energy
B.
linear momentum
C.
angular momentum
D.
force
Ans:
energy
Explanation :
The Planck's constant (h) can be defined as a pro-portionality constant that relates the energy (E) of a photon to the frequency (?) of its associated electro-magnetic wave. Mathematically, Planck's Constant (h) = Energy (E)/frequency (?). The Planck constant is named after Max Planck, the instigator of quantum theory, who discovered it in 1900.
[9] When number of turns in a coil is tripled, without any change in the length of coil, its self inductance becomes?
A.
Nine times
B.
Three times
C.
Six times
D.
One-third
Ans:
Nine times
Explanation :
0
[10] The abbreviation LHC stands for which machine?
A.
Light Heat Collider
B.
Large Hadron Collider
C.
Long Heavy Collider
D.
Large High Collider
Ans:
Large Hadron Collider
Explanation :
LHC stands for Large Hadron Collider is the world's largest and most powerful particle collider that allows scientists to further test the properties of the Higgs boson. It lies in a tunnel beneath the France- Switzerland border near Geneva, Switzerland.
[11] Which of the following have the same unit?
A.
Work and power
B.
Torque and moment of inertia
C.
Work and torque
D.
Torque and angular momentum
Ans:
Work and torque
Explanation :
The SI unit of work is the Newton-metre or joule (J). A Newton meter is also the SI unit of torque (also called "moment" or "moment of force").
[12] In a particular system, the units of length, mass and time are chosen to be 10 cm, 10 g and 0.1 s respectively. The unit of force in this system will be equivalent to –
A.
0.1 N
B.
1 N
C.
10 N
D.
100 N
Ans:
0.1 N
Explanation :
0
[13] Relative humidity is expressed as –
A.
Grams
B.
Kilograms
C.
Percentage
D.
Ratio
Ans:
Percentage
Explanation :
Relative humidity is the amount of moisture in the air compared to what the air can "hold" at that temperature. It signifies the mass of water vapour present in the air expressed as a percentage of the mass that would be present in an equal volume of saturated air at the same temperature.
[14] Why is weightlessness experienced while orbiting the earth in space ships?
A.
Inertia
B.
Acceleration
C.
Zero gravity
D.
None of these
Ans:
None of these
Explanation :
The reason astronauts experience weightlessness which orbiting the earth in spaceships is that they are in free fall. A spacecraft in orbit is falling towards the Earth, because of gravity, but it is moving forward in its orbit fast enough that the path it follows is a curve that is a closed ellipse.
[15] Where is a transistor most likely to be found?
A.
Wrist watch
B.
Fuse
C.
Hearing aid
D.
Fluorescent lamp
Ans:
Hearing aid
Explanation :
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. The transistor invented in 1948 was well suited to the hearing aid application due to low power and small size; hearing aids were an early adopter of transistors. Transistors replaced the need for batteries in hearing aids
[16] What is the SI unit of electric current?
A.
Amperes
B.
Coulombs
C.
Joules
D.
Watts
Ans:
Amperes
Explanation :
The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second.
[17] An object is in static equilibrium when it is .
A.
at rest
B.
moving in a circular path
C.
moving with uniform velocity
D.
accelerating at high speed
Ans:
at rest
Explanation :
When forces acting on an object which is at rest are balanced, the object is said to be in a state of static equilibrium. The resultant of these forces equals zero.
[18] Equal volumes of different gases at any definite temperature and pressure have-
A.
Equal weights
B.
equal masses
C.
equal density
D.
equal no. of molecules
Ans:
equal no. of molecules
Explanation :
At equal volume of different gases at any definite temperature and pressure have equal no. of particles.
[19] Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings"?
A.
Doppler's Effect
B.
Newton's law of cooling
C.
Kirchhoff's Law
D.
Stefan's Law
Ans:
Newton's law of cooling
Explanation :
Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature.
[20] Which of the following reaction is the main cause of energy radiated from Sun?
A.
Nuclear fission
B.
Nuclear fusion
C.
Chemical reaction
D.
Diffusion reaction
Ans:
Nuclear fusion
Explanation :
The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.
[21] Every hot object emits –
A.
X-rays
B.
Visible light
C.
Infrared rays
D.
Ultraviolet rays
Ans:
Infrared rays
Explanation :
As per Planck's law, all objects emit electromagnetic radiation according to their temperature. Colder objects emit waves with very low frequency (such, as radio or microwaves), while hot objects emit infra- red rays or even ultraviolet and higher frequencies. At room temperature, most of the radiation is in the infra-red region.
[22] Postage Meter was invented by -
A.
Fyodor Pirotsky
B.
Arthur Pitney
C.
Fritz Pfleumer
D.
Stephen Perry
Ans:
Arthur Pitney
Explanation :
The first postal meter to be commercially produced and distributed was invented by Arthur Pitney. World's first postage meter on December 9, 1901.
[23] A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
A.
increase
B.
decrease
C.
remain unaffected
D.
have its shape changed
Ans:
increase
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
Energy conversion. n. (General Physics) is the process of changing one form of energy into another, such as nuclear energy into heat or solar energy into electrical energy.
[4] The washing machine works on the principle of –
A.
Dialysis
B.
Diffusion
C.
Reverse osmosis
D.
Centrifugation
Ans:
Centrifugation
Explanation :
Washing machines work on the principle of centrifugation. They are based on medium sized centrifuges that put an object in rotation around a fixed axis, applying force perpendicular to the axis.
[5] The 'Choke' used with a tube light is basically –
A.
an inductor
B.
a capacitor
C.
a transformer
D.
a resistor
Ans:
an inductor
Explanation :
In electronics, a choke is an inductor used to block higher-frequency alternating current (AC) in an electrical circuit, while passing lower-frequency or direct current (DC). In a tubelight, the high voltage is created by suddenly interrupting the current in choke, which is connected in series with the tubelight.
[6] The temperature of a liquid is 32° F. What is its temperature in Celsius scale?
A.
32° C
B.
0° C
C.
100° C
D.
212° C
Ans:
0° C
Explanation :
The formulas for converting between degree Celsius and degree Fahrenheit are: °F = °C 9/5 + 32 and °C = (°F - 32) 5/9. So in Celsius scale, 32o F= 0° C
[7] Which of the following phenomenon helps to conclude that light is a transverse wave?
A.
interference
B.
diffraction
C.
polarization
D.
refraction
Ans:
polarization
Explanation :
The phenomena of interference and diffraction of light were successful beyond doubt to prove that light is a form of wave. But they failed to decide whether light is transverse or longitudinal wave. The fact that light is a transverse wave was established only after the discovery of the phenomenon of polarization.
[8] Plank's constant has the dimensions of :
A.
energy
B.
linear momentum
C.
angular momentum
D.
force
Ans:
energy
Explanation :
The Planck's constant (h) can be defined as a pro-portionality constant that relates the energy (E) of a photon to the frequency (?) of its associated electro-magnetic wave. Mathematically, Planck's Constant (h) = Energy (E)/frequency (?). The Planck constant is named after Max Planck, the instigator of quantum theory, who discovered it in 1900.
[9] When number of turns in a coil is tripled, without any change in the length of coil, its self inductance becomes?
A.
Nine times
B.
Three times
C.
Six times
D.
One-third
Ans:
Nine times
Explanation :
0
[10] The abbreviation LHC stands for which machine?
A.
Light Heat Collider
B.
Large Hadron Collider
C.
Long Heavy Collider
D.
Large High Collider
Ans:
Large Hadron Collider
Explanation :
LHC stands for Large Hadron Collider is the world's largest and most powerful particle collider that allows scientists to further test the properties of the Higgs boson. It lies in a tunnel beneath the France- Switzerland border near Geneva, Switzerland.
[11] Which of the following have the same unit?
A.
Work and power
B.
Torque and moment of inertia
C.
Work and torque
D.
Torque and angular momentum
Ans:
Work and torque
Explanation :
The SI unit of work is the Newton-metre or joule (J). A Newton meter is also the SI unit of torque (also called "moment" or "moment of force").
[12] In a particular system, the units of length, mass and time are chosen to be 10 cm, 10 g and 0.1 s respectively. The unit of force in this system will be equivalent to –
A.
0.1 N
B.
1 N
C.
10 N
D.
100 N
Ans:
0.1 N
Explanation :
0
[13] Relative humidity is expressed as –
A.
Grams
B.
Kilograms
C.
Percentage
D.
Ratio
Ans:
Percentage
Explanation :
Relative humidity is the amount of moisture in the air compared to what the air can "hold" at that temperature. It signifies the mass of water vapour present in the air expressed as a percentage of the mass that would be present in an equal volume of saturated air at the same temperature.
[14] Why is weightlessness experienced while orbiting the earth in space ships?
A.
Inertia
B.
Acceleration
C.
Zero gravity
D.
None of these
Ans:
None of these
Explanation :
The reason astronauts experience weightlessness which orbiting the earth in spaceships is that they are in free fall. A spacecraft in orbit is falling towards the Earth, because of gravity, but it is moving forward in its orbit fast enough that the path it follows is a curve that is a closed ellipse.
[15] Where is a transistor most likely to be found?
A.
Wrist watch
B.
Fuse
C.
Hearing aid
D.
Fluorescent lamp
Ans:
Hearing aid
Explanation :
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. The transistor invented in 1948 was well suited to the hearing aid application due to low power and small size; hearing aids were an early adopter of transistors. Transistors replaced the need for batteries in hearing aids
[16] What is the SI unit of electric current?
A.
Amperes
B.
Coulombs
C.
Joules
D.
Watts
Ans:
Amperes
Explanation :
The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second.
[17] An object is in static equilibrium when it is .
A.
at rest
B.
moving in a circular path
C.
moving with uniform velocity
D.
accelerating at high speed
Ans:
at rest
Explanation :
When forces acting on an object which is at rest are balanced, the object is said to be in a state of static equilibrium. The resultant of these forces equals zero.
[18] Equal volumes of different gases at any definite temperature and pressure have-
A.
Equal weights
B.
equal masses
C.
equal density
D.
equal no. of molecules
Ans:
equal no. of molecules
Explanation :
At equal volume of different gases at any definite temperature and pressure have equal no. of particles.
[19] Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings"?
A.
Doppler's Effect
B.
Newton's law of cooling
C.
Kirchhoff's Law
D.
Stefan's Law
Ans:
Newton's law of cooling
Explanation :
Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature.
[20] Which of the following reaction is the main cause of energy radiated from Sun?
A.
Nuclear fission
B.
Nuclear fusion
C.
Chemical reaction
D.
Diffusion reaction
Ans:
Nuclear fusion
Explanation :
The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.
[21] Every hot object emits –
A.
X-rays
B.
Visible light
C.
Infrared rays
D.
Ultraviolet rays
Ans:
Infrared rays
Explanation :
As per Planck's law, all objects emit electromagnetic radiation according to their temperature. Colder objects emit waves with very low frequency (such, as radio or microwaves), while hot objects emit infra- red rays or even ultraviolet and higher frequencies. At room temperature, most of the radiation is in the infra-red region.
[22] Postage Meter was invented by -
A.
Fyodor Pirotsky
B.
Arthur Pitney
C.
Fritz Pfleumer
D.
Stephen Perry
Ans:
Arthur Pitney
Explanation :
The first postal meter to be commercially produced and distributed was invented by Arthur Pitney. World's first postage meter on December 9, 1901.
[23] A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
A.
increase
B.
decrease
C.
remain unaffected
D.
have its shape changed
Ans:
increase
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
In electronics, a choke is an inductor used to block higher-frequency alternating current (AC) in an electrical circuit, while passing lower-frequency or direct current (DC). In a tubelight, the high voltage is created by suddenly interrupting the current in choke, which is connected in series with the tubelight.
[6] The temperature of a liquid is 32° F. What is its temperature in Celsius scale?
A.
32° C
B.
0° C
C.
100° C
D.
212° C
Ans:
0° C
Explanation :
The formulas for converting between degree Celsius and degree Fahrenheit are: °F = °C 9/5 + 32 and °C = (°F - 32) 5/9. So in Celsius scale, 32o F= 0° C
[7] Which of the following phenomenon helps to conclude that light is a transverse wave?
A.
interference
B.
diffraction
C.
polarization
D.
refraction
Ans:
polarization
Explanation :
The phenomena of interference and diffraction of light were successful beyond doubt to prove that light is a form of wave. But they failed to decide whether light is transverse or longitudinal wave. The fact that light is a transverse wave was established only after the discovery of the phenomenon of polarization.
[8] Plank's constant has the dimensions of :
A.
energy
B.
linear momentum
C.
angular momentum
D.
force
Ans:
energy
Explanation :
The Planck's constant (h) can be defined as a pro-portionality constant that relates the energy (E) of a photon to the frequency (?) of its associated electro-magnetic wave. Mathematically, Planck's Constant (h) = Energy (E)/frequency (?). The Planck constant is named after Max Planck, the instigator of quantum theory, who discovered it in 1900.
[9] When number of turns in a coil is tripled, without any change in the length of coil, its self inductance becomes?
A.
Nine times
B.
Three times
C.
Six times
D.
One-third
Ans:
Nine times
Explanation :
0
[10] The abbreviation LHC stands for which machine?
A.
Light Heat Collider
B.
Large Hadron Collider
C.
Long Heavy Collider
D.
Large High Collider
Ans:
Large Hadron Collider
Explanation :
LHC stands for Large Hadron Collider is the world's largest and most powerful particle collider that allows scientists to further test the properties of the Higgs boson. It lies in a tunnel beneath the France- Switzerland border near Geneva, Switzerland.
[11] Which of the following have the same unit?
A.
Work and power
B.
Torque and moment of inertia
C.
Work and torque
D.
Torque and angular momentum
Ans:
Work and torque
Explanation :
The SI unit of work is the Newton-metre or joule (J). A Newton meter is also the SI unit of torque (also called "moment" or "moment of force").
[12] In a particular system, the units of length, mass and time are chosen to be 10 cm, 10 g and 0.1 s respectively. The unit of force in this system will be equivalent to –
A.
0.1 N
B.
1 N
C.
10 N
D.
100 N
Ans:
0.1 N
Explanation :
0
[13] Relative humidity is expressed as –
A.
Grams
B.
Kilograms
C.
Percentage
D.
Ratio
Ans:
Percentage
Explanation :
Relative humidity is the amount of moisture in the air compared to what the air can "hold" at that temperature. It signifies the mass of water vapour present in the air expressed as a percentage of the mass that would be present in an equal volume of saturated air at the same temperature.
[14] Why is weightlessness experienced while orbiting the earth in space ships?
A.
Inertia
B.
Acceleration
C.
Zero gravity
D.
None of these
Ans:
None of these
Explanation :
The reason astronauts experience weightlessness which orbiting the earth in spaceships is that they are in free fall. A spacecraft in orbit is falling towards the Earth, because of gravity, but it is moving forward in its orbit fast enough that the path it follows is a curve that is a closed ellipse.
[15] Where is a transistor most likely to be found?
A.
Wrist watch
B.
Fuse
C.
Hearing aid
D.
Fluorescent lamp
Ans:
Hearing aid
Explanation :
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. The transistor invented in 1948 was well suited to the hearing aid application due to low power and small size; hearing aids were an early adopter of transistors. Transistors replaced the need for batteries in hearing aids
[16] What is the SI unit of electric current?
A.
Amperes
B.
Coulombs
C.
Joules
D.
Watts
Ans:
Amperes
Explanation :
The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second.
[17] An object is in static equilibrium when it is .
A.
at rest
B.
moving in a circular path
C.
moving with uniform velocity
D.
accelerating at high speed
Ans:
at rest
Explanation :
When forces acting on an object which is at rest are balanced, the object is said to be in a state of static equilibrium. The resultant of these forces equals zero.
[18] Equal volumes of different gases at any definite temperature and pressure have-
A.
Equal weights
B.
equal masses
C.
equal density
D.
equal no. of molecules
Ans:
equal no. of molecules
Explanation :
At equal volume of different gases at any definite temperature and pressure have equal no. of particles.
[19] Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings"?
A.
Doppler's Effect
B.
Newton's law of cooling
C.
Kirchhoff's Law
D.
Stefan's Law
Ans:
Newton's law of cooling
Explanation :
Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature.
[20] Which of the following reaction is the main cause of energy radiated from Sun?
A.
Nuclear fission
B.
Nuclear fusion
C.
Chemical reaction
D.
Diffusion reaction
Ans:
Nuclear fusion
Explanation :
The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.
[21] Every hot object emits –
A.
X-rays
B.
Visible light
C.
Infrared rays
D.
Ultraviolet rays
Ans:
Infrared rays
Explanation :
As per Planck's law, all objects emit electromagnetic radiation according to their temperature. Colder objects emit waves with very low frequency (such, as radio or microwaves), while hot objects emit infra- red rays or even ultraviolet and higher frequencies. At room temperature, most of the radiation is in the infra-red region.
[22] Postage Meter was invented by -
A.
Fyodor Pirotsky
B.
Arthur Pitney
C.
Fritz Pfleumer
D.
Stephen Perry
Ans:
Arthur Pitney
Explanation :
The first postal meter to be commercially produced and distributed was invented by Arthur Pitney. World's first postage meter on December 9, 1901.
[23] A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
A.
increase
B.
decrease
C.
remain unaffected
D.
have its shape changed
Ans:
increase
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
The phenomena of interference and diffraction of light were successful beyond doubt to prove that light is a form of wave. But they failed to decide whether light is transverse or longitudinal wave. The fact that light is a transverse wave was established only after the discovery of the phenomenon of polarization.
[8] Plank's constant has the dimensions of :
A.
energy
B.
linear momentum
C.
angular momentum
D.
force
Ans:
energy
Explanation :
The Planck's constant (h) can be defined as a pro-portionality constant that relates the energy (E) of a photon to the frequency (?) of its associated electro-magnetic wave. Mathematically, Planck's Constant (h) = Energy (E)/frequency (?). The Planck constant is named after Max Planck, the instigator of quantum theory, who discovered it in 1900.
[9] When number of turns in a coil is tripled, without any change in the length of coil, its self inductance becomes?
A.
Nine times
B.
Three times
C.
Six times
D.
One-third
Ans:
Nine times
Explanation :
0
[10] The abbreviation LHC stands for which machine?
A.
Light Heat Collider
B.
Large Hadron Collider
C.
Long Heavy Collider
D.
Large High Collider
Ans:
Large Hadron Collider
Explanation :
LHC stands for Large Hadron Collider is the world's largest and most powerful particle collider that allows scientists to further test the properties of the Higgs boson. It lies in a tunnel beneath the France- Switzerland border near Geneva, Switzerland.
[11] Which of the following have the same unit?
A.
Work and power
B.
Torque and moment of inertia
C.
Work and torque
D.
Torque and angular momentum
Ans:
Work and torque
Explanation :
The SI unit of work is the Newton-metre or joule (J). A Newton meter is also the SI unit of torque (also called "moment" or "moment of force").
[12] In a particular system, the units of length, mass and time are chosen to be 10 cm, 10 g and 0.1 s respectively. The unit of force in this system will be equivalent to –
A.
0.1 N
B.
1 N
C.
10 N
D.
100 N
Ans:
0.1 N
Explanation :
0
[13] Relative humidity is expressed as –
A.
Grams
B.
Kilograms
C.
Percentage
D.
Ratio
Ans:
Percentage
Explanation :
Relative humidity is the amount of moisture in the air compared to what the air can "hold" at that temperature. It signifies the mass of water vapour present in the air expressed as a percentage of the mass that would be present in an equal volume of saturated air at the same temperature.
[14] Why is weightlessness experienced while orbiting the earth in space ships?
A.
Inertia
B.
Acceleration
C.
Zero gravity
D.
None of these
Ans:
None of these
Explanation :
The reason astronauts experience weightlessness which orbiting the earth in spaceships is that they are in free fall. A spacecraft in orbit is falling towards the Earth, because of gravity, but it is moving forward in its orbit fast enough that the path it follows is a curve that is a closed ellipse.
[15] Where is a transistor most likely to be found?
A.
Wrist watch
B.
Fuse
C.
Hearing aid
D.
Fluorescent lamp
Ans:
Hearing aid
Explanation :
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. The transistor invented in 1948 was well suited to the hearing aid application due to low power and small size; hearing aids were an early adopter of transistors. Transistors replaced the need for batteries in hearing aids
[16] What is the SI unit of electric current?
A.
Amperes
B.
Coulombs
C.
Joules
D.
Watts
Ans:
Amperes
Explanation :
The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second.
[17] An object is in static equilibrium when it is .
A.
at rest
B.
moving in a circular path
C.
moving with uniform velocity
D.
accelerating at high speed
Ans:
at rest
Explanation :
When forces acting on an object which is at rest are balanced, the object is said to be in a state of static equilibrium. The resultant of these forces equals zero.
[18] Equal volumes of different gases at any definite temperature and pressure have-
A.
Equal weights
B.
equal masses
C.
equal density
D.
equal no. of molecules
Ans:
equal no. of molecules
Explanation :
At equal volume of different gases at any definite temperature and pressure have equal no. of particles.
[19] Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings"?
A.
Doppler's Effect
B.
Newton's law of cooling
C.
Kirchhoff's Law
D.
Stefan's Law
Ans:
Newton's law of cooling
Explanation :
Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature.
[20] Which of the following reaction is the main cause of energy radiated from Sun?
A.
Nuclear fission
B.
Nuclear fusion
C.
Chemical reaction
D.
Diffusion reaction
Ans:
Nuclear fusion
Explanation :
The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.
[21] Every hot object emits –
A.
X-rays
B.
Visible light
C.
Infrared rays
D.
Ultraviolet rays
Ans:
Infrared rays
Explanation :
As per Planck's law, all objects emit electromagnetic radiation according to their temperature. Colder objects emit waves with very low frequency (such, as radio or microwaves), while hot objects emit infra- red rays or even ultraviolet and higher frequencies. At room temperature, most of the radiation is in the infra-red region.
[22] Postage Meter was invented by -
A.
Fyodor Pirotsky
B.
Arthur Pitney
C.
Fritz Pfleumer
D.
Stephen Perry
Ans:
Arthur Pitney
Explanation :
The first postal meter to be commercially produced and distributed was invented by Arthur Pitney. World's first postage meter on December 9, 1901.
[23] A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
A.
increase
B.
decrease
C.
remain unaffected
D.
have its shape changed
Ans:
increase
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
0
[10] The abbreviation LHC stands for which machine?
A.
Light Heat Collider
B.
Large Hadron Collider
C.
Long Heavy Collider
D.
Large High Collider
Ans:
Large Hadron Collider
Explanation :
LHC stands for Large Hadron Collider is the world's largest and most powerful particle collider that allows scientists to further test the properties of the Higgs boson. It lies in a tunnel beneath the France- Switzerland border near Geneva, Switzerland.
[11] Which of the following have the same unit?
A.
Work and power
B.
Torque and moment of inertia
C.
Work and torque
D.
Torque and angular momentum
Ans:
Work and torque
Explanation :
The SI unit of work is the Newton-metre or joule (J). A Newton meter is also the SI unit of torque (also called "moment" or "moment of force").
[12] In a particular system, the units of length, mass and time are chosen to be 10 cm, 10 g and 0.1 s respectively. The unit of force in this system will be equivalent to –
A.
0.1 N
B.
1 N
C.
10 N
D.
100 N
Ans:
0.1 N
Explanation :
0
[13] Relative humidity is expressed as –
A.
Grams
B.
Kilograms
C.
Percentage
D.
Ratio
Ans:
Percentage
Explanation :
Relative humidity is the amount of moisture in the air compared to what the air can "hold" at that temperature. It signifies the mass of water vapour present in the air expressed as a percentage of the mass that would be present in an equal volume of saturated air at the same temperature.
[14] Why is weightlessness experienced while orbiting the earth in space ships?
A.
Inertia
B.
Acceleration
C.
Zero gravity
D.
None of these
Ans:
None of these
Explanation :
The reason astronauts experience weightlessness which orbiting the earth in spaceships is that they are in free fall. A spacecraft in orbit is falling towards the Earth, because of gravity, but it is moving forward in its orbit fast enough that the path it follows is a curve that is a closed ellipse.
[15] Where is a transistor most likely to be found?
A.
Wrist watch
B.
Fuse
C.
Hearing aid
D.
Fluorescent lamp
Ans:
Hearing aid
Explanation :
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. The transistor invented in 1948 was well suited to the hearing aid application due to low power and small size; hearing aids were an early adopter of transistors. Transistors replaced the need for batteries in hearing aids
[16] What is the SI unit of electric current?
A.
Amperes
B.
Coulombs
C.
Joules
D.
Watts
Ans:
Amperes
Explanation :
The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second.
[17] An object is in static equilibrium when it is .
A.
at rest
B.
moving in a circular path
C.
moving with uniform velocity
D.
accelerating at high speed
Ans:
at rest
Explanation :
When forces acting on an object which is at rest are balanced, the object is said to be in a state of static equilibrium. The resultant of these forces equals zero.
[18] Equal volumes of different gases at any definite temperature and pressure have-
A.
Equal weights
B.
equal masses
C.
equal density
D.
equal no. of molecules
Ans:
equal no. of molecules
Explanation :
At equal volume of different gases at any definite temperature and pressure have equal no. of particles.
[19] Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings"?
A.
Doppler's Effect
B.
Newton's law of cooling
C.
Kirchhoff's Law
D.
Stefan's Law
Ans:
Newton's law of cooling
Explanation :
Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature.
[20] Which of the following reaction is the main cause of energy radiated from Sun?
A.
Nuclear fission
B.
Nuclear fusion
C.
Chemical reaction
D.
Diffusion reaction
Ans:
Nuclear fusion
Explanation :
The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.
[21] Every hot object emits –
A.
X-rays
B.
Visible light
C.
Infrared rays
D.
Ultraviolet rays
Ans:
Infrared rays
Explanation :
As per Planck's law, all objects emit electromagnetic radiation according to their temperature. Colder objects emit waves with very low frequency (such, as radio or microwaves), while hot objects emit infra- red rays or even ultraviolet and higher frequencies. At room temperature, most of the radiation is in the infra-red region.
[22] Postage Meter was invented by -
A.
Fyodor Pirotsky
B.
Arthur Pitney
C.
Fritz Pfleumer
D.
Stephen Perry
Ans:
Arthur Pitney
Explanation :
The first postal meter to be commercially produced and distributed was invented by Arthur Pitney. World's first postage meter on December 9, 1901.
[23] A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
A.
increase
B.
decrease
C.
remain unaffected
D.
have its shape changed
Ans:
increase
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
The SI unit of work is the Newton-metre or joule (J). A Newton meter is also the SI unit of torque (also called "moment" or "moment of force").
[12] In a particular system, the units of length, mass and time are chosen to be 10 cm, 10 g and 0.1 s respectively. The unit of force in this system will be equivalent to –
A.
0.1 N
B.
1 N
C.
10 N
D.
100 N
Ans:
0.1 N
Explanation :
0
[13] Relative humidity is expressed as –
A.
Grams
B.
Kilograms
C.
Percentage
D.
Ratio
Ans:
Percentage
Explanation :
Relative humidity is the amount of moisture in the air compared to what the air can "hold" at that temperature. It signifies the mass of water vapour present in the air expressed as a percentage of the mass that would be present in an equal volume of saturated air at the same temperature.
[14] Why is weightlessness experienced while orbiting the earth in space ships?
A.
Inertia
B.
Acceleration
C.
Zero gravity
D.
None of these
Ans:
None of these
Explanation :
The reason astronauts experience weightlessness which orbiting the earth in spaceships is that they are in free fall. A spacecraft in orbit is falling towards the Earth, because of gravity, but it is moving forward in its orbit fast enough that the path it follows is a curve that is a closed ellipse.
[15] Where is a transistor most likely to be found?
A.
Wrist watch
B.
Fuse
C.
Hearing aid
D.
Fluorescent lamp
Ans:
Hearing aid
Explanation :
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. The transistor invented in 1948 was well suited to the hearing aid application due to low power and small size; hearing aids were an early adopter of transistors. Transistors replaced the need for batteries in hearing aids
[16] What is the SI unit of electric current?
A.
Amperes
B.
Coulombs
C.
Joules
D.
Watts
Ans:
Amperes
Explanation :
The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second.
[17] An object is in static equilibrium when it is .
A.
at rest
B.
moving in a circular path
C.
moving with uniform velocity
D.
accelerating at high speed
Ans:
at rest
Explanation :
When forces acting on an object which is at rest are balanced, the object is said to be in a state of static equilibrium. The resultant of these forces equals zero.
[18] Equal volumes of different gases at any definite temperature and pressure have-
A.
Equal weights
B.
equal masses
C.
equal density
D.
equal no. of molecules
Ans:
equal no. of molecules
Explanation :
At equal volume of different gases at any definite temperature and pressure have equal no. of particles.
[19] Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings"?
A.
Doppler's Effect
B.
Newton's law of cooling
C.
Kirchhoff's Law
D.
Stefan's Law
Ans:
Newton's law of cooling
Explanation :
Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature.
[20] Which of the following reaction is the main cause of energy radiated from Sun?
A.
Nuclear fission
B.
Nuclear fusion
C.
Chemical reaction
D.
Diffusion reaction
Ans:
Nuclear fusion
Explanation :
The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.
[21] Every hot object emits –
A.
X-rays
B.
Visible light
C.
Infrared rays
D.
Ultraviolet rays
Ans:
Infrared rays
Explanation :
As per Planck's law, all objects emit electromagnetic radiation according to their temperature. Colder objects emit waves with very low frequency (such, as radio or microwaves), while hot objects emit infra- red rays or even ultraviolet and higher frequencies. At room temperature, most of the radiation is in the infra-red region.
[22] Postage Meter was invented by -
A.
Fyodor Pirotsky
B.
Arthur Pitney
C.
Fritz Pfleumer
D.
Stephen Perry
Ans:
Arthur Pitney
Explanation :
The first postal meter to be commercially produced and distributed was invented by Arthur Pitney. World's first postage meter on December 9, 1901.
[23] A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
A.
increase
B.
decrease
C.
remain unaffected
D.
have its shape changed
Ans:
increase
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
Relative humidity is the amount of moisture in the air compared to what the air can "hold" at that temperature. It signifies the mass of water vapour present in the air expressed as a percentage of the mass that would be present in an equal volume of saturated air at the same temperature.
[14] Why is weightlessness experienced while orbiting the earth in space ships?
A.
Inertia
B.
Acceleration
C.
Zero gravity
D.
None of these
Ans:
None of these
Explanation :
The reason astronauts experience weightlessness which orbiting the earth in spaceships is that they are in free fall. A spacecraft in orbit is falling towards the Earth, because of gravity, but it is moving forward in its orbit fast enough that the path it follows is a curve that is a closed ellipse.
[15] Where is a transistor most likely to be found?
A.
Wrist watch
B.
Fuse
C.
Hearing aid
D.
Fluorescent lamp
Ans:
Hearing aid
Explanation :
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. The transistor invented in 1948 was well suited to the hearing aid application due to low power and small size; hearing aids were an early adopter of transistors. Transistors replaced the need for batteries in hearing aids
[16] What is the SI unit of electric current?
A.
Amperes
B.
Coulombs
C.
Joules
D.
Watts
Ans:
Amperes
Explanation :
The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second.
[17] An object is in static equilibrium when it is .
A.
at rest
B.
moving in a circular path
C.
moving with uniform velocity
D.
accelerating at high speed
Ans:
at rest
Explanation :
When forces acting on an object which is at rest are balanced, the object is said to be in a state of static equilibrium. The resultant of these forces equals zero.
[18] Equal volumes of different gases at any definite temperature and pressure have-
A.
Equal weights
B.
equal masses
C.
equal density
D.
equal no. of molecules
Ans:
equal no. of molecules
Explanation :
At equal volume of different gases at any definite temperature and pressure have equal no. of particles.
[19] Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings"?
A.
Doppler's Effect
B.
Newton's law of cooling
C.
Kirchhoff's Law
D.
Stefan's Law
Ans:
Newton's law of cooling
Explanation :
Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature.
[20] Which of the following reaction is the main cause of energy radiated from Sun?
A.
Nuclear fission
B.
Nuclear fusion
C.
Chemical reaction
D.
Diffusion reaction
Ans:
Nuclear fusion
Explanation :
The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.
[21] Every hot object emits –
A.
X-rays
B.
Visible light
C.
Infrared rays
D.
Ultraviolet rays
Ans:
Infrared rays
Explanation :
As per Planck's law, all objects emit electromagnetic radiation according to their temperature. Colder objects emit waves with very low frequency (such, as radio or microwaves), while hot objects emit infra- red rays or even ultraviolet and higher frequencies. At room temperature, most of the radiation is in the infra-red region.
[22] Postage Meter was invented by -
A.
Fyodor Pirotsky
B.
Arthur Pitney
C.
Fritz Pfleumer
D.
Stephen Perry
Ans:
Arthur Pitney
Explanation :
The first postal meter to be commercially produced and distributed was invented by Arthur Pitney. World's first postage meter on December 9, 1901.
[23] A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
A.
increase
B.
decrease
C.
remain unaffected
D.
have its shape changed
Ans:
increase
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. The transistor invented in 1948 was well suited to the hearing aid application due to low power and small size; hearing aids were an early adopter of transistors. Transistors replaced the need for batteries in hearing aids
[16] What is the SI unit of electric current?
A.
Amperes
B.
Coulombs
C.
Joules
D.
Watts
Ans:
Amperes
Explanation :
The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second.
[17] An object is in static equilibrium when it is .
A.
at rest
B.
moving in a circular path
C.
moving with uniform velocity
D.
accelerating at high speed
Ans:
at rest
Explanation :
When forces acting on an object which is at rest are balanced, the object is said to be in a state of static equilibrium. The resultant of these forces equals zero.
[18] Equal volumes of different gases at any definite temperature and pressure have-
A.
Equal weights
B.
equal masses
C.
equal density
D.
equal no. of molecules
Ans:
equal no. of molecules
Explanation :
At equal volume of different gases at any definite temperature and pressure have equal no. of particles.
[19] Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings"?
A.
Doppler's Effect
B.
Newton's law of cooling
C.
Kirchhoff's Law
D.
Stefan's Law
Ans:
Newton's law of cooling
Explanation :
Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature.
[20] Which of the following reaction is the main cause of energy radiated from Sun?
A.
Nuclear fission
B.
Nuclear fusion
C.
Chemical reaction
D.
Diffusion reaction
Ans:
Nuclear fusion
Explanation :
The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.
[21] Every hot object emits –
A.
X-rays
B.
Visible light
C.
Infrared rays
D.
Ultraviolet rays
Ans:
Infrared rays
Explanation :
As per Planck's law, all objects emit electromagnetic radiation according to their temperature. Colder objects emit waves with very low frequency (such, as radio or microwaves), while hot objects emit infra- red rays or even ultraviolet and higher frequencies. At room temperature, most of the radiation is in the infra-red region.
[22] Postage Meter was invented by -
A.
Fyodor Pirotsky
B.
Arthur Pitney
C.
Fritz Pfleumer
D.
Stephen Perry
Ans:
Arthur Pitney
Explanation :
The first postal meter to be commercially produced and distributed was invented by Arthur Pitney. World's first postage meter on December 9, 1901.
[23] A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
A.
increase
B.
decrease
C.
remain unaffected
D.
have its shape changed
Ans:
increase
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
When forces acting on an object which is at rest are balanced, the object is said to be in a state of static equilibrium. The resultant of these forces equals zero.
[18] Equal volumes of different gases at any definite temperature and pressure have-
A.
Equal weights
B.
equal masses
C.
equal density
D.
equal no. of molecules
Ans:
equal no. of molecules
Explanation :
At equal volume of different gases at any definite temperature and pressure have equal no. of particles.
[19] Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings"?
A.
Doppler's Effect
B.
Newton's law of cooling
C.
Kirchhoff's Law
D.
Stefan's Law
Ans:
Newton's law of cooling
Explanation :
Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature.
[20] Which of the following reaction is the main cause of energy radiated from Sun?
A.
Nuclear fission
B.
Nuclear fusion
C.
Chemical reaction
D.
Diffusion reaction
Ans:
Nuclear fusion
Explanation :
The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.
[21] Every hot object emits –
A.
X-rays
B.
Visible light
C.
Infrared rays
D.
Ultraviolet rays
Ans:
Infrared rays
Explanation :
As per Planck's law, all objects emit electromagnetic radiation according to their temperature. Colder objects emit waves with very low frequency (such, as radio or microwaves), while hot objects emit infra- red rays or even ultraviolet and higher frequencies. At room temperature, most of the radiation is in the infra-red region.
[22] Postage Meter was invented by -
A.
Fyodor Pirotsky
B.
Arthur Pitney
C.
Fritz Pfleumer
D.
Stephen Perry
Ans:
Arthur Pitney
Explanation :
The first postal meter to be commercially produced and distributed was invented by Arthur Pitney. World's first postage meter on December 9, 1901.
[23] A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
A.
increase
B.
decrease
C.
remain unaffected
D.
have its shape changed
Ans:
increase
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature.
[20] Which of the following reaction is the main cause of energy radiated from Sun?
A.
Nuclear fission
B.
Nuclear fusion
C.
Chemical reaction
D.
Diffusion reaction
Ans:
Nuclear fusion
Explanation :
The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.
[21] Every hot object emits –
A.
X-rays
B.
Visible light
C.
Infrared rays
D.
Ultraviolet rays
Ans:
Infrared rays
Explanation :
As per Planck's law, all objects emit electromagnetic radiation according to their temperature. Colder objects emit waves with very low frequency (such, as radio or microwaves), while hot objects emit infra- red rays or even ultraviolet and higher frequencies. At room temperature, most of the radiation is in the infra-red region.
[22] Postage Meter was invented by -
A.
Fyodor Pirotsky
B.
Arthur Pitney
C.
Fritz Pfleumer
D.
Stephen Perry
Ans:
Arthur Pitney
Explanation :
The first postal meter to be commercially produced and distributed was invented by Arthur Pitney. World's first postage meter on December 9, 1901.
[23] A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
A.
increase
B.
decrease
C.
remain unaffected
D.
have its shape changed
Ans:
increase
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
As per Planck's law, all objects emit electromagnetic radiation according to their temperature. Colder objects emit waves with very low frequency (such, as radio or microwaves), while hot objects emit infra- red rays or even ultraviolet and higher frequencies. At room temperature, most of the radiation is in the infra-red region.
[22] Postage Meter was invented by -
A.
Fyodor Pirotsky
B.
Arthur Pitney
C.
Fritz Pfleumer
D.
Stephen Perry
Ans:
Arthur Pitney
Explanation :
The first postal meter to be commercially produced and distributed was invented by Arthur Pitney. World's first postage meter on December 9, 1901.
[23] A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
A.
increase
B.
decrease
C.
remain unaffected
D.
have its shape changed
Ans:
increase
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius.
[24] When two semiconductors of p-and n-type are brought in contact, they form p-n junction which acts like a/an –
A.
Conductor
B.
Oscillator
C.
Rectifier
D.
Amplifier
Ans:
Rectifier
Explanation :
P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it acts as an rectifier device to convert sinusoidal current to unidirection. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
[25] Ohm's law is valid in case of –
A.
semiconductor
B.
conductor
C.
superconductor
D.
insulator
Ans:
conductor
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Explanation :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.