[1] Supercooling is cooling of liquid _.
A.
below melting point
B.
below freezing point
C.
at melting point
D.
above melting point
Ans:
below freezing point
Explanation :
Supercooling, also known as undercooling, is the process of lowering the temperature of a liquid or a gas below its freezing point without it becoming a solid. A good example of this phenomenon is clouds in high altitude that are an accumulation of supercooled droplets of water below their freezing point. Refrigeration is a popular commercial application of supercooling.
[2] How can we measure specific gravity of milk?
A.
Using a viscometer
B.
Using an odometer
C.
Using a hygrometer
D.
Using a hydrometer
Ans:
Using a hydrometer
Explanation :
A hydrometer is an instrument that measures the specific gravity of liquids the ratio of the density of the liquid to the density of water.
[3] The base of an electric iron is brightly polished mainly -
A.
to make it smooth and frictionless
B.
to make it rust-proof
C.
to reduce heat loss by radiation
D.
to make it more durable
Ans:
to reduce heat loss by radiation
Explanation :
Polished surfaces are poor radiators of heat. So loss of heat on that account is reduced and the electric iron remains hotter than otherwise.
[4] Oparin's theary about origin of life' is related to -
A.
chemical evolution
B.
physical evolution
C.
biological evolution
D.
artificial evolution
Ans:
chemical evolution
Explanation :
Alexander Oparin was a Russian biochemist, notable for his contributions to the theory of the origin of life on Earth, and particularly for the primordial soup theory of the evolution of life from carbon-based molecules.
[5] Heat given to a body which raises its temperature by 1°C is known as -
A.
water equivalent
B.
thermal capacity
C.
specific heat
D.
temperature gradient
Ans:
thermal capacity
Explanation :
Heat capacity or thermal capacity is a measurable physical quantity equal to the ratio of the heat added to (or removed from) an object to the resulting temperature change.
[6] Flemings "Left hand Rule" is associated with the effect of –
A.
Electric field on current
B.
Magnetic field on magnet
C.
Electric field on magnet
D.
Magnetic Field on current
Ans:
Magnetic Field on current
Explanation :
Whenever, a current carrying conductor comes under a magnetic field, there will be force acting on the conductor and on the other hand, if a conductor is forcefully brought under a magnetic field, there will be an induced current in that conductor. In both of the phenomenon, there is a relation between magnetic field, current and force.
[7] The force which makes a vehicle to stop when break is applied is called –
A.
gravitational force
B.
vanderwalls force
C.
frictional force
D.
covalent force
Ans:
frictional force
Explanation :
A brake is a mechanical device that inhibits motion by absorbing energy from a moving system. It is used for slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of friction. When the brakes are applied, work is done by the friction force between the brakes and the wheels.
[8] In radio-communication, the signals emitted by transmitting antenna are reflected on –
A.
stratosphere
B.
ozonosphere
C.
ionosphere
D.
troposphere
Ans:
ionosphere
Explanation :
The lower atmosphere is more or less transparent to radio waves. However, the ionosphere reflects back the radio waves. Thus, a signal emitted by an antenna from a certain place can be received at another place on the surface of Earth in the following two ways: ground wave propagation and sky wave propagation.
[9] While cooking, if the bottom of the vessel is getting blackened on the outside, it means that -
A.
The food is not cooked completely
B.
The fuel is not burning completely
C.
The fuel is wet
D.
The fuel is burning completely
Ans:
The fuel is not burning completely
Explanation :
While cooking, if the bottom of the vessel is getting blackened on the outside, it means that the fuel is not burning completely. When the fuel burns completely giving a blue flame, the bottom of the vessel remains clean. When the fuel does not burn completely then a sooty flame appears which makes the bottom of the utensil black. It is due to the air holes, which are getting blocked and the fuel does not burn completely.
[10] If electrical conductivity increases with the increase of temperature of a substance, then it is a -
A.
Conductor
B.
Semiconductor
C.
Insulator
D.
Carborator
Ans:
Semiconductor
Explanation :
A solid substance that has conductivity between that of an insulator and that of most metals, either due to the addition of an impurity or because of temperature effects.
[11] Automatic wrist watches get energy from -
A.
twist in spring
B.
liquid crystal
C.
kinetic energy
D.
movement of our hands
Ans:
twist in spring
Explanation :
An automatic watch is a watch that continues to operate due to the regular motion of the wearer's wrist.
[12] Radian is used to measure -
A.
Temperature
B.
Intensity of Flame
C.
Angle
D.
Solid Angle
Ans:
Angle
Explanation :
Kelvin is used to measure Temperature, Candela is used to measure Intensity of flame, Steredian is used to measure Solid Angle.
[13] Which one of the following types of glass can cut off ultraviolet rays?
A.
Soda glass
B.
Pyrex glass
C.
Jena glass
D.
Crookes glass
Ans:
Crookes glass
Explanation :
In this glass mainly cerium oxide (CiO2) is present which sharply absorbs the ultraviolet rays from the sunlight so utilized in making lenses of eye glasses.
[14] Light year is a unit of –
A.
Light
B.
Current
C.
Distance
D.
Time
Ans:
Distance
Explanation :
A light-year is a unit of length used informally to express astronomical distances. It is equal to just under 10 trillion kilometres.
[15] The word 'insulation' means –
A.
matters which insulate
B.
incoming solar radiation
C.
insoluble matters
D.
None of the above
Ans:
incoming solar radiation
Explanation :
Insolation is the solar radiation that reaches the earth’s surface. It is measured by the amount of solar energy received per square centimeter per minute. Insolation affects temperature. The more the insolation, the higher is the temperature.
[16] Which of the following is not a vector quantity?
A.
Speed
B.
Velocity
C.
Torque
D.
Displacement
Ans:
Speed
Explanation :
Speed is a scalar quantity that refers to "how fast an object is moving." Speed can be thought of as the rate at which an object covers distance. It does not keep track of direction. In contrast, velocity is a vector quantity as it is direction aware.
[17] An object with a constant speed –
A.
is not accelerated
B.
might be accelerated
C.
is always accelerated
D.
also has a constant velocity
Ans:
is not accelerated
Explanation :
Acceleration is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. An object with constant speed will have no acceleration as the speed is uniform.
[18] The instrument used to regulate temperature to a particular degree is called :
A.
Thermostat
B.
Thermometer
C.
Pyrometer
D.
Thermocouple
Ans:
Thermostat
Explanation :
A thermostat is a component which senses the temperature of a system so that the system's temperature is maintained near a desired set point. At its core, a thermostat is simply the controls used to regulate temperature in a heating system.
[19] The power dissipated in a resistance is given by?
A.
V²/R
B.
IV
C.
All of these
D.
I²R
Ans:
All of these
Explanation :
Any resistor in a circuit that has a voltage drop across it dissipates electrical power. This electrical power is converted into heat energy hence all resistors have a power rating.
[20] The technique used by bats to find their way or to locate food is _.
A.
SONAR
B.
RADAR
C.
Echolocation
D.
Flapping
Ans:
Echolocation
Explanation :
Bats use echolocation to navigate and find food in the dark. To echolocate, bats send out sound waves from their mouth or nose. When the sound waves hit an object they produce echoes.
[21] In the absence of the earth's atmosphere, sky would appear –
A.
blue
B.
deep red
C.
white
D.
black
Ans:
black
Explanation :
Sky appears blue because the tiny particles of the earth's atmosphere scatter the blue colour (short wavelength) of the sunlight more dominantly than other wavelengths. A blue sky is a manifestation of Rayleigh scatter. The sky would appear black in the absence of earth's atmosphere because there would be no particles to scatter the light.
[22] If ice floating on water in a vessel melts, the water level in the vessel -
A.
increases
B.
does not change
C.
first increases before decreasing
D.
decreases
Ans:
does not change
Explanation :
When ice floating on water in a vessel melts, the water level in the vessel does not change. This is because when floating, the ice displaces an amount of water equal to its mass, and when melted, it becomes an amount of water equal to its mass. It is accordance with Archimedes Principle, which states that the mass of the liquid displaced by a floating object is equivalent to the mass of the object.
[23] One micron is equal to-
A.
1/10th of mm
B.
1/100th of mm
C.
1/1000th of mm
D.
1/10000th of mm
Ans:
1/1000th of mm
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
Supercooling, also known as undercooling, is the process of lowering the temperature of a liquid or a gas below its freezing point without it becoming a solid. A good example of this phenomenon is clouds in high altitude that are an accumulation of supercooled droplets of water below their freezing point. Refrigeration is a popular commercial application of supercooling.
[2] How can we measure specific gravity of milk?
A.
Using a viscometer
B.
Using an odometer
C.
Using a hygrometer
D.
Using a hydrometer
Ans:
Using a hydrometer
Explanation :
A hydrometer is an instrument that measures the specific gravity of liquids the ratio of the density of the liquid to the density of water.
[3] The base of an electric iron is brightly polished mainly -
A.
to make it smooth and frictionless
B.
to make it rust-proof
C.
to reduce heat loss by radiation
D.
to make it more durable
Ans:
to reduce heat loss by radiation
Explanation :
Polished surfaces are poor radiators of heat. So loss of heat on that account is reduced and the electric iron remains hotter than otherwise.
[4] Oparin's theary about origin of life' is related to -
A.
chemical evolution
B.
physical evolution
C.
biological evolution
D.
artificial evolution
Ans:
chemical evolution
Explanation :
Alexander Oparin was a Russian biochemist, notable for his contributions to the theory of the origin of life on Earth, and particularly for the primordial soup theory of the evolution of life from carbon-based molecules.
[5] Heat given to a body which raises its temperature by 1°C is known as -
A.
water equivalent
B.
thermal capacity
C.
specific heat
D.
temperature gradient
Ans:
thermal capacity
Explanation :
Heat capacity or thermal capacity is a measurable physical quantity equal to the ratio of the heat added to (or removed from) an object to the resulting temperature change.
[6] Flemings "Left hand Rule" is associated with the effect of –
A.
Electric field on current
B.
Magnetic field on magnet
C.
Electric field on magnet
D.
Magnetic Field on current
Ans:
Magnetic Field on current
Explanation :
Whenever, a current carrying conductor comes under a magnetic field, there will be force acting on the conductor and on the other hand, if a conductor is forcefully brought under a magnetic field, there will be an induced current in that conductor. In both of the phenomenon, there is a relation between magnetic field, current and force.
[7] The force which makes a vehicle to stop when break is applied is called –
A.
gravitational force
B.
vanderwalls force
C.
frictional force
D.
covalent force
Ans:
frictional force
Explanation :
A brake is a mechanical device that inhibits motion by absorbing energy from a moving system. It is used for slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of friction. When the brakes are applied, work is done by the friction force between the brakes and the wheels.
[8] In radio-communication, the signals emitted by transmitting antenna are reflected on –
A.
stratosphere
B.
ozonosphere
C.
ionosphere
D.
troposphere
Ans:
ionosphere
Explanation :
The lower atmosphere is more or less transparent to radio waves. However, the ionosphere reflects back the radio waves. Thus, a signal emitted by an antenna from a certain place can be received at another place on the surface of Earth in the following two ways: ground wave propagation and sky wave propagation.
[9] While cooking, if the bottom of the vessel is getting blackened on the outside, it means that -
A.
The food is not cooked completely
B.
The fuel is not burning completely
C.
The fuel is wet
D.
The fuel is burning completely
Ans:
The fuel is not burning completely
Explanation :
While cooking, if the bottom of the vessel is getting blackened on the outside, it means that the fuel is not burning completely. When the fuel burns completely giving a blue flame, the bottom of the vessel remains clean. When the fuel does not burn completely then a sooty flame appears which makes the bottom of the utensil black. It is due to the air holes, which are getting blocked and the fuel does not burn completely.
[10] If electrical conductivity increases with the increase of temperature of a substance, then it is a -
A.
Conductor
B.
Semiconductor
C.
Insulator
D.
Carborator
Ans:
Semiconductor
Explanation :
A solid substance that has conductivity between that of an insulator and that of most metals, either due to the addition of an impurity or because of temperature effects.
[11] Automatic wrist watches get energy from -
A.
twist in spring
B.
liquid crystal
C.
kinetic energy
D.
movement of our hands
Ans:
twist in spring
Explanation :
An automatic watch is a watch that continues to operate due to the regular motion of the wearer's wrist.
[12] Radian is used to measure -
A.
Temperature
B.
Intensity of Flame
C.
Angle
D.
Solid Angle
Ans:
Angle
Explanation :
Kelvin is used to measure Temperature, Candela is used to measure Intensity of flame, Steredian is used to measure Solid Angle.
[13] Which one of the following types of glass can cut off ultraviolet rays?
A.
Soda glass
B.
Pyrex glass
C.
Jena glass
D.
Crookes glass
Ans:
Crookes glass
Explanation :
In this glass mainly cerium oxide (CiO2) is present which sharply absorbs the ultraviolet rays from the sunlight so utilized in making lenses of eye glasses.
[14] Light year is a unit of –
A.
Light
B.
Current
C.
Distance
D.
Time
Ans:
Distance
Explanation :
A light-year is a unit of length used informally to express astronomical distances. It is equal to just under 10 trillion kilometres.
[15] The word 'insulation' means –
A.
matters which insulate
B.
incoming solar radiation
C.
insoluble matters
D.
None of the above
Ans:
incoming solar radiation
Explanation :
Insolation is the solar radiation that reaches the earth’s surface. It is measured by the amount of solar energy received per square centimeter per minute. Insolation affects temperature. The more the insolation, the higher is the temperature.
[16] Which of the following is not a vector quantity?
A.
Speed
B.
Velocity
C.
Torque
D.
Displacement
Ans:
Speed
Explanation :
Speed is a scalar quantity that refers to "how fast an object is moving." Speed can be thought of as the rate at which an object covers distance. It does not keep track of direction. In contrast, velocity is a vector quantity as it is direction aware.
[17] An object with a constant speed –
A.
is not accelerated
B.
might be accelerated
C.
is always accelerated
D.
also has a constant velocity
Ans:
is not accelerated
Explanation :
Acceleration is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. An object with constant speed will have no acceleration as the speed is uniform.
[18] The instrument used to regulate temperature to a particular degree is called :
A.
Thermostat
B.
Thermometer
C.
Pyrometer
D.
Thermocouple
Ans:
Thermostat
Explanation :
A thermostat is a component which senses the temperature of a system so that the system's temperature is maintained near a desired set point. At its core, a thermostat is simply the controls used to regulate temperature in a heating system.
[19] The power dissipated in a resistance is given by?
A.
V²/R
B.
IV
C.
All of these
D.
I²R
Ans:
All of these
Explanation :
Any resistor in a circuit that has a voltage drop across it dissipates electrical power. This electrical power is converted into heat energy hence all resistors have a power rating.
[20] The technique used by bats to find their way or to locate food is _.
A.
SONAR
B.
RADAR
C.
Echolocation
D.
Flapping
Ans:
Echolocation
Explanation :
Bats use echolocation to navigate and find food in the dark. To echolocate, bats send out sound waves from their mouth or nose. When the sound waves hit an object they produce echoes.
[21] In the absence of the earth's atmosphere, sky would appear –
A.
blue
B.
deep red
C.
white
D.
black
Ans:
black
Explanation :
Sky appears blue because the tiny particles of the earth's atmosphere scatter the blue colour (short wavelength) of the sunlight more dominantly than other wavelengths. A blue sky is a manifestation of Rayleigh scatter. The sky would appear black in the absence of earth's atmosphere because there would be no particles to scatter the light.
[22] If ice floating on water in a vessel melts, the water level in the vessel -
A.
increases
B.
does not change
C.
first increases before decreasing
D.
decreases
Ans:
does not change
Explanation :
When ice floating on water in a vessel melts, the water level in the vessel does not change. This is because when floating, the ice displaces an amount of water equal to its mass, and when melted, it becomes an amount of water equal to its mass. It is accordance with Archimedes Principle, which states that the mass of the liquid displaced by a floating object is equivalent to the mass of the object.
[23] One micron is equal to-
A.
1/10th of mm
B.
1/100th of mm
C.
1/1000th of mm
D.
1/10000th of mm
Ans:
1/1000th of mm
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
Polished surfaces are poor radiators of heat. So loss of heat on that account is reduced and the electric iron remains hotter than otherwise.
[4] Oparin's theary about origin of life' is related to -
A.
chemical evolution
B.
physical evolution
C.
biological evolution
D.
artificial evolution
Ans:
chemical evolution
Explanation :
Alexander Oparin was a Russian biochemist, notable for his contributions to the theory of the origin of life on Earth, and particularly for the primordial soup theory of the evolution of life from carbon-based molecules.
[5] Heat given to a body which raises its temperature by 1°C is known as -
A.
water equivalent
B.
thermal capacity
C.
specific heat
D.
temperature gradient
Ans:
thermal capacity
Explanation :
Heat capacity or thermal capacity is a measurable physical quantity equal to the ratio of the heat added to (or removed from) an object to the resulting temperature change.
[6] Flemings "Left hand Rule" is associated with the effect of –
A.
Electric field on current
B.
Magnetic field on magnet
C.
Electric field on magnet
D.
Magnetic Field on current
Ans:
Magnetic Field on current
Explanation :
Whenever, a current carrying conductor comes under a magnetic field, there will be force acting on the conductor and on the other hand, if a conductor is forcefully brought under a magnetic field, there will be an induced current in that conductor. In both of the phenomenon, there is a relation between magnetic field, current and force.
[7] The force which makes a vehicle to stop when break is applied is called –
A.
gravitational force
B.
vanderwalls force
C.
frictional force
D.
covalent force
Ans:
frictional force
Explanation :
A brake is a mechanical device that inhibits motion by absorbing energy from a moving system. It is used for slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of friction. When the brakes are applied, work is done by the friction force between the brakes and the wheels.
[8] In radio-communication, the signals emitted by transmitting antenna are reflected on –
A.
stratosphere
B.
ozonosphere
C.
ionosphere
D.
troposphere
Ans:
ionosphere
Explanation :
The lower atmosphere is more or less transparent to radio waves. However, the ionosphere reflects back the radio waves. Thus, a signal emitted by an antenna from a certain place can be received at another place on the surface of Earth in the following two ways: ground wave propagation and sky wave propagation.
[9] While cooking, if the bottom of the vessel is getting blackened on the outside, it means that -
A.
The food is not cooked completely
B.
The fuel is not burning completely
C.
The fuel is wet
D.
The fuel is burning completely
Ans:
The fuel is not burning completely
Explanation :
While cooking, if the bottom of the vessel is getting blackened on the outside, it means that the fuel is not burning completely. When the fuel burns completely giving a blue flame, the bottom of the vessel remains clean. When the fuel does not burn completely then a sooty flame appears which makes the bottom of the utensil black. It is due to the air holes, which are getting blocked and the fuel does not burn completely.
[10] If electrical conductivity increases with the increase of temperature of a substance, then it is a -
A.
Conductor
B.
Semiconductor
C.
Insulator
D.
Carborator
Ans:
Semiconductor
Explanation :
A solid substance that has conductivity between that of an insulator and that of most metals, either due to the addition of an impurity or because of temperature effects.
[11] Automatic wrist watches get energy from -
A.
twist in spring
B.
liquid crystal
C.
kinetic energy
D.
movement of our hands
Ans:
twist in spring
Explanation :
An automatic watch is a watch that continues to operate due to the regular motion of the wearer's wrist.
[12] Radian is used to measure -
A.
Temperature
B.
Intensity of Flame
C.
Angle
D.
Solid Angle
Ans:
Angle
Explanation :
Kelvin is used to measure Temperature, Candela is used to measure Intensity of flame, Steredian is used to measure Solid Angle.
[13] Which one of the following types of glass can cut off ultraviolet rays?
A.
Soda glass
B.
Pyrex glass
C.
Jena glass
D.
Crookes glass
Ans:
Crookes glass
Explanation :
In this glass mainly cerium oxide (CiO2) is present which sharply absorbs the ultraviolet rays from the sunlight so utilized in making lenses of eye glasses.
[14] Light year is a unit of –
A.
Light
B.
Current
C.
Distance
D.
Time
Ans:
Distance
Explanation :
A light-year is a unit of length used informally to express astronomical distances. It is equal to just under 10 trillion kilometres.
[15] The word 'insulation' means –
A.
matters which insulate
B.
incoming solar radiation
C.
insoluble matters
D.
None of the above
Ans:
incoming solar radiation
Explanation :
Insolation is the solar radiation that reaches the earth’s surface. It is measured by the amount of solar energy received per square centimeter per minute. Insolation affects temperature. The more the insolation, the higher is the temperature.
[16] Which of the following is not a vector quantity?
A.
Speed
B.
Velocity
C.
Torque
D.
Displacement
Ans:
Speed
Explanation :
Speed is a scalar quantity that refers to "how fast an object is moving." Speed can be thought of as the rate at which an object covers distance. It does not keep track of direction. In contrast, velocity is a vector quantity as it is direction aware.
[17] An object with a constant speed –
A.
is not accelerated
B.
might be accelerated
C.
is always accelerated
D.
also has a constant velocity
Ans:
is not accelerated
Explanation :
Acceleration is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. An object with constant speed will have no acceleration as the speed is uniform.
[18] The instrument used to regulate temperature to a particular degree is called :
A.
Thermostat
B.
Thermometer
C.
Pyrometer
D.
Thermocouple
Ans:
Thermostat
Explanation :
A thermostat is a component which senses the temperature of a system so that the system's temperature is maintained near a desired set point. At its core, a thermostat is simply the controls used to regulate temperature in a heating system.
[19] The power dissipated in a resistance is given by?
A.
V²/R
B.
IV
C.
All of these
D.
I²R
Ans:
All of these
Explanation :
Any resistor in a circuit that has a voltage drop across it dissipates electrical power. This electrical power is converted into heat energy hence all resistors have a power rating.
[20] The technique used by bats to find their way or to locate food is _.
A.
SONAR
B.
RADAR
C.
Echolocation
D.
Flapping
Ans:
Echolocation
Explanation :
Bats use echolocation to navigate and find food in the dark. To echolocate, bats send out sound waves from their mouth or nose. When the sound waves hit an object they produce echoes.
[21] In the absence of the earth's atmosphere, sky would appear –
A.
blue
B.
deep red
C.
white
D.
black
Ans:
black
Explanation :
Sky appears blue because the tiny particles of the earth's atmosphere scatter the blue colour (short wavelength) of the sunlight more dominantly than other wavelengths. A blue sky is a manifestation of Rayleigh scatter. The sky would appear black in the absence of earth's atmosphere because there would be no particles to scatter the light.
[22] If ice floating on water in a vessel melts, the water level in the vessel -
A.
increases
B.
does not change
C.
first increases before decreasing
D.
decreases
Ans:
does not change
Explanation :
When ice floating on water in a vessel melts, the water level in the vessel does not change. This is because when floating, the ice displaces an amount of water equal to its mass, and when melted, it becomes an amount of water equal to its mass. It is accordance with Archimedes Principle, which states that the mass of the liquid displaced by a floating object is equivalent to the mass of the object.
[23] One micron is equal to-
A.
1/10th of mm
B.
1/100th of mm
C.
1/1000th of mm
D.
1/10000th of mm
Ans:
1/1000th of mm
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
Heat capacity or thermal capacity is a measurable physical quantity equal to the ratio of the heat added to (or removed from) an object to the resulting temperature change.
[6] Flemings "Left hand Rule" is associated with the effect of –
A.
Electric field on current
B.
Magnetic field on magnet
C.
Electric field on magnet
D.
Magnetic Field on current
Ans:
Magnetic Field on current
Explanation :
Whenever, a current carrying conductor comes under a magnetic field, there will be force acting on the conductor and on the other hand, if a conductor is forcefully brought under a magnetic field, there will be an induced current in that conductor. In both of the phenomenon, there is a relation between magnetic field, current and force.
[7] The force which makes a vehicle to stop when break is applied is called –
A.
gravitational force
B.
vanderwalls force
C.
frictional force
D.
covalent force
Ans:
frictional force
Explanation :
A brake is a mechanical device that inhibits motion by absorbing energy from a moving system. It is used for slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of friction. When the brakes are applied, work is done by the friction force between the brakes and the wheels.
[8] In radio-communication, the signals emitted by transmitting antenna are reflected on –
A.
stratosphere
B.
ozonosphere
C.
ionosphere
D.
troposphere
Ans:
ionosphere
Explanation :
The lower atmosphere is more or less transparent to radio waves. However, the ionosphere reflects back the radio waves. Thus, a signal emitted by an antenna from a certain place can be received at another place on the surface of Earth in the following two ways: ground wave propagation and sky wave propagation.
[9] While cooking, if the bottom of the vessel is getting blackened on the outside, it means that -
A.
The food is not cooked completely
B.
The fuel is not burning completely
C.
The fuel is wet
D.
The fuel is burning completely
Ans:
The fuel is not burning completely
Explanation :
While cooking, if the bottom of the vessel is getting blackened on the outside, it means that the fuel is not burning completely. When the fuel burns completely giving a blue flame, the bottom of the vessel remains clean. When the fuel does not burn completely then a sooty flame appears which makes the bottom of the utensil black. It is due to the air holes, which are getting blocked and the fuel does not burn completely.
[10] If electrical conductivity increases with the increase of temperature of a substance, then it is a -
A.
Conductor
B.
Semiconductor
C.
Insulator
D.
Carborator
Ans:
Semiconductor
Explanation :
A solid substance that has conductivity between that of an insulator and that of most metals, either due to the addition of an impurity or because of temperature effects.
[11] Automatic wrist watches get energy from -
A.
twist in spring
B.
liquid crystal
C.
kinetic energy
D.
movement of our hands
Ans:
twist in spring
Explanation :
An automatic watch is a watch that continues to operate due to the regular motion of the wearer's wrist.
[12] Radian is used to measure -
A.
Temperature
B.
Intensity of Flame
C.
Angle
D.
Solid Angle
Ans:
Angle
Explanation :
Kelvin is used to measure Temperature, Candela is used to measure Intensity of flame, Steredian is used to measure Solid Angle.
[13] Which one of the following types of glass can cut off ultraviolet rays?
A.
Soda glass
B.
Pyrex glass
C.
Jena glass
D.
Crookes glass
Ans:
Crookes glass
Explanation :
In this glass mainly cerium oxide (CiO2) is present which sharply absorbs the ultraviolet rays from the sunlight so utilized in making lenses of eye glasses.
[14] Light year is a unit of –
A.
Light
B.
Current
C.
Distance
D.
Time
Ans:
Distance
Explanation :
A light-year is a unit of length used informally to express astronomical distances. It is equal to just under 10 trillion kilometres.
[15] The word 'insulation' means –
A.
matters which insulate
B.
incoming solar radiation
C.
insoluble matters
D.
None of the above
Ans:
incoming solar radiation
Explanation :
Insolation is the solar radiation that reaches the earth’s surface. It is measured by the amount of solar energy received per square centimeter per minute. Insolation affects temperature. The more the insolation, the higher is the temperature.
[16] Which of the following is not a vector quantity?
A.
Speed
B.
Velocity
C.
Torque
D.
Displacement
Ans:
Speed
Explanation :
Speed is a scalar quantity that refers to "how fast an object is moving." Speed can be thought of as the rate at which an object covers distance. It does not keep track of direction. In contrast, velocity is a vector quantity as it is direction aware.
[17] An object with a constant speed –
A.
is not accelerated
B.
might be accelerated
C.
is always accelerated
D.
also has a constant velocity
Ans:
is not accelerated
Explanation :
Acceleration is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. An object with constant speed will have no acceleration as the speed is uniform.
[18] The instrument used to regulate temperature to a particular degree is called :
A.
Thermostat
B.
Thermometer
C.
Pyrometer
D.
Thermocouple
Ans:
Thermostat
Explanation :
A thermostat is a component which senses the temperature of a system so that the system's temperature is maintained near a desired set point. At its core, a thermostat is simply the controls used to regulate temperature in a heating system.
[19] The power dissipated in a resistance is given by?
A.
V²/R
B.
IV
C.
All of these
D.
I²R
Ans:
All of these
Explanation :
Any resistor in a circuit that has a voltage drop across it dissipates electrical power. This electrical power is converted into heat energy hence all resistors have a power rating.
[20] The technique used by bats to find their way or to locate food is _.
A.
SONAR
B.
RADAR
C.
Echolocation
D.
Flapping
Ans:
Echolocation
Explanation :
Bats use echolocation to navigate and find food in the dark. To echolocate, bats send out sound waves from their mouth or nose. When the sound waves hit an object they produce echoes.
[21] In the absence of the earth's atmosphere, sky would appear –
A.
blue
B.
deep red
C.
white
D.
black
Ans:
black
Explanation :
Sky appears blue because the tiny particles of the earth's atmosphere scatter the blue colour (short wavelength) of the sunlight more dominantly than other wavelengths. A blue sky is a manifestation of Rayleigh scatter. The sky would appear black in the absence of earth's atmosphere because there would be no particles to scatter the light.
[22] If ice floating on water in a vessel melts, the water level in the vessel -
A.
increases
B.
does not change
C.
first increases before decreasing
D.
decreases
Ans:
does not change
Explanation :
When ice floating on water in a vessel melts, the water level in the vessel does not change. This is because when floating, the ice displaces an amount of water equal to its mass, and when melted, it becomes an amount of water equal to its mass. It is accordance with Archimedes Principle, which states that the mass of the liquid displaced by a floating object is equivalent to the mass of the object.
[23] One micron is equal to-
A.
1/10th of mm
B.
1/100th of mm
C.
1/1000th of mm
D.
1/10000th of mm
Ans:
1/1000th of mm
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
A brake is a mechanical device that inhibits motion by absorbing energy from a moving system. It is used for slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of friction. When the brakes are applied, work is done by the friction force between the brakes and the wheels.
[8] In radio-communication, the signals emitted by transmitting antenna are reflected on –
A.
stratosphere
B.
ozonosphere
C.
ionosphere
D.
troposphere
Ans:
ionosphere
Explanation :
The lower atmosphere is more or less transparent to radio waves. However, the ionosphere reflects back the radio waves. Thus, a signal emitted by an antenna from a certain place can be received at another place on the surface of Earth in the following two ways: ground wave propagation and sky wave propagation.
[9] While cooking, if the bottom of the vessel is getting blackened on the outside, it means that -
A.
The food is not cooked completely
B.
The fuel is not burning completely
C.
The fuel is wet
D.
The fuel is burning completely
Ans:
The fuel is not burning completely
Explanation :
While cooking, if the bottom of the vessel is getting blackened on the outside, it means that the fuel is not burning completely. When the fuel burns completely giving a blue flame, the bottom of the vessel remains clean. When the fuel does not burn completely then a sooty flame appears which makes the bottom of the utensil black. It is due to the air holes, which are getting blocked and the fuel does not burn completely.
[10] If electrical conductivity increases with the increase of temperature of a substance, then it is a -
A.
Conductor
B.
Semiconductor
C.
Insulator
D.
Carborator
Ans:
Semiconductor
Explanation :
A solid substance that has conductivity between that of an insulator and that of most metals, either due to the addition of an impurity or because of temperature effects.
[11] Automatic wrist watches get energy from -
A.
twist in spring
B.
liquid crystal
C.
kinetic energy
D.
movement of our hands
Ans:
twist in spring
Explanation :
An automatic watch is a watch that continues to operate due to the regular motion of the wearer's wrist.
[12] Radian is used to measure -
A.
Temperature
B.
Intensity of Flame
C.
Angle
D.
Solid Angle
Ans:
Angle
Explanation :
Kelvin is used to measure Temperature, Candela is used to measure Intensity of flame, Steredian is used to measure Solid Angle.
[13] Which one of the following types of glass can cut off ultraviolet rays?
A.
Soda glass
B.
Pyrex glass
C.
Jena glass
D.
Crookes glass
Ans:
Crookes glass
Explanation :
In this glass mainly cerium oxide (CiO2) is present which sharply absorbs the ultraviolet rays from the sunlight so utilized in making lenses of eye glasses.
[14] Light year is a unit of –
A.
Light
B.
Current
C.
Distance
D.
Time
Ans:
Distance
Explanation :
A light-year is a unit of length used informally to express astronomical distances. It is equal to just under 10 trillion kilometres.
[15] The word 'insulation' means –
A.
matters which insulate
B.
incoming solar radiation
C.
insoluble matters
D.
None of the above
Ans:
incoming solar radiation
Explanation :
Insolation is the solar radiation that reaches the earth’s surface. It is measured by the amount of solar energy received per square centimeter per minute. Insolation affects temperature. The more the insolation, the higher is the temperature.
[16] Which of the following is not a vector quantity?
A.
Speed
B.
Velocity
C.
Torque
D.
Displacement
Ans:
Speed
Explanation :
Speed is a scalar quantity that refers to "how fast an object is moving." Speed can be thought of as the rate at which an object covers distance. It does not keep track of direction. In contrast, velocity is a vector quantity as it is direction aware.
[17] An object with a constant speed –
A.
is not accelerated
B.
might be accelerated
C.
is always accelerated
D.
also has a constant velocity
Ans:
is not accelerated
Explanation :
Acceleration is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. An object with constant speed will have no acceleration as the speed is uniform.
[18] The instrument used to regulate temperature to a particular degree is called :
A.
Thermostat
B.
Thermometer
C.
Pyrometer
D.
Thermocouple
Ans:
Thermostat
Explanation :
A thermostat is a component which senses the temperature of a system so that the system's temperature is maintained near a desired set point. At its core, a thermostat is simply the controls used to regulate temperature in a heating system.
[19] The power dissipated in a resistance is given by?
A.
V²/R
B.
IV
C.
All of these
D.
I²R
Ans:
All of these
Explanation :
Any resistor in a circuit that has a voltage drop across it dissipates electrical power. This electrical power is converted into heat energy hence all resistors have a power rating.
[20] The technique used by bats to find their way or to locate food is _.
A.
SONAR
B.
RADAR
C.
Echolocation
D.
Flapping
Ans:
Echolocation
Explanation :
Bats use echolocation to navigate and find food in the dark. To echolocate, bats send out sound waves from their mouth or nose. When the sound waves hit an object they produce echoes.
[21] In the absence of the earth's atmosphere, sky would appear –
A.
blue
B.
deep red
C.
white
D.
black
Ans:
black
Explanation :
Sky appears blue because the tiny particles of the earth's atmosphere scatter the blue colour (short wavelength) of the sunlight more dominantly than other wavelengths. A blue sky is a manifestation of Rayleigh scatter. The sky would appear black in the absence of earth's atmosphere because there would be no particles to scatter the light.
[22] If ice floating on water in a vessel melts, the water level in the vessel -
A.
increases
B.
does not change
C.
first increases before decreasing
D.
decreases
Ans:
does not change
Explanation :
When ice floating on water in a vessel melts, the water level in the vessel does not change. This is because when floating, the ice displaces an amount of water equal to its mass, and when melted, it becomes an amount of water equal to its mass. It is accordance with Archimedes Principle, which states that the mass of the liquid displaced by a floating object is equivalent to the mass of the object.
[23] One micron is equal to-
A.
1/10th of mm
B.
1/100th of mm
C.
1/1000th of mm
D.
1/10000th of mm
Ans:
1/1000th of mm
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
While cooking, if the bottom of the vessel is getting blackened on the outside, it means that the fuel is not burning completely. When the fuel burns completely giving a blue flame, the bottom of the vessel remains clean. When the fuel does not burn completely then a sooty flame appears which makes the bottom of the utensil black. It is due to the air holes, which are getting blocked and the fuel does not burn completely.
[10] If electrical conductivity increases with the increase of temperature of a substance, then it is a -
A.
Conductor
B.
Semiconductor
C.
Insulator
D.
Carborator
Ans:
Semiconductor
Explanation :
A solid substance that has conductivity between that of an insulator and that of most metals, either due to the addition of an impurity or because of temperature effects.
[11] Automatic wrist watches get energy from -
A.
twist in spring
B.
liquid crystal
C.
kinetic energy
D.
movement of our hands
Ans:
twist in spring
Explanation :
An automatic watch is a watch that continues to operate due to the regular motion of the wearer's wrist.
[12] Radian is used to measure -
A.
Temperature
B.
Intensity of Flame
C.
Angle
D.
Solid Angle
Ans:
Angle
Explanation :
Kelvin is used to measure Temperature, Candela is used to measure Intensity of flame, Steredian is used to measure Solid Angle.
[13] Which one of the following types of glass can cut off ultraviolet rays?
A.
Soda glass
B.
Pyrex glass
C.
Jena glass
D.
Crookes glass
Ans:
Crookes glass
Explanation :
In this glass mainly cerium oxide (CiO2) is present which sharply absorbs the ultraviolet rays from the sunlight so utilized in making lenses of eye glasses.
[14] Light year is a unit of –
A.
Light
B.
Current
C.
Distance
D.
Time
Ans:
Distance
Explanation :
A light-year is a unit of length used informally to express astronomical distances. It is equal to just under 10 trillion kilometres.
[15] The word 'insulation' means –
A.
matters which insulate
B.
incoming solar radiation
C.
insoluble matters
D.
None of the above
Ans:
incoming solar radiation
Explanation :
Insolation is the solar radiation that reaches the earth’s surface. It is measured by the amount of solar energy received per square centimeter per minute. Insolation affects temperature. The more the insolation, the higher is the temperature.
[16] Which of the following is not a vector quantity?
A.
Speed
B.
Velocity
C.
Torque
D.
Displacement
Ans:
Speed
Explanation :
Speed is a scalar quantity that refers to "how fast an object is moving." Speed can be thought of as the rate at which an object covers distance. It does not keep track of direction. In contrast, velocity is a vector quantity as it is direction aware.
[17] An object with a constant speed –
A.
is not accelerated
B.
might be accelerated
C.
is always accelerated
D.
also has a constant velocity
Ans:
is not accelerated
Explanation :
Acceleration is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. An object with constant speed will have no acceleration as the speed is uniform.
[18] The instrument used to regulate temperature to a particular degree is called :
A.
Thermostat
B.
Thermometer
C.
Pyrometer
D.
Thermocouple
Ans:
Thermostat
Explanation :
A thermostat is a component which senses the temperature of a system so that the system's temperature is maintained near a desired set point. At its core, a thermostat is simply the controls used to regulate temperature in a heating system.
[19] The power dissipated in a resistance is given by?
A.
V²/R
B.
IV
C.
All of these
D.
I²R
Ans:
All of these
Explanation :
Any resistor in a circuit that has a voltage drop across it dissipates electrical power. This electrical power is converted into heat energy hence all resistors have a power rating.
[20] The technique used by bats to find their way or to locate food is _.
A.
SONAR
B.
RADAR
C.
Echolocation
D.
Flapping
Ans:
Echolocation
Explanation :
Bats use echolocation to navigate and find food in the dark. To echolocate, bats send out sound waves from their mouth or nose. When the sound waves hit an object they produce echoes.
[21] In the absence of the earth's atmosphere, sky would appear –
A.
blue
B.
deep red
C.
white
D.
black
Ans:
black
Explanation :
Sky appears blue because the tiny particles of the earth's atmosphere scatter the blue colour (short wavelength) of the sunlight more dominantly than other wavelengths. A blue sky is a manifestation of Rayleigh scatter. The sky would appear black in the absence of earth's atmosphere because there would be no particles to scatter the light.
[22] If ice floating on water in a vessel melts, the water level in the vessel -
A.
increases
B.
does not change
C.
first increases before decreasing
D.
decreases
Ans:
does not change
Explanation :
When ice floating on water in a vessel melts, the water level in the vessel does not change. This is because when floating, the ice displaces an amount of water equal to its mass, and when melted, it becomes an amount of water equal to its mass. It is accordance with Archimedes Principle, which states that the mass of the liquid displaced by a floating object is equivalent to the mass of the object.
[23] One micron is equal to-
A.
1/10th of mm
B.
1/100th of mm
C.
1/1000th of mm
D.
1/10000th of mm
Ans:
1/1000th of mm
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
An automatic watch is a watch that continues to operate due to the regular motion of the wearer's wrist.
[12] Radian is used to measure -
A.
Temperature
B.
Intensity of Flame
C.
Angle
D.
Solid Angle
Ans:
Angle
Explanation :
Kelvin is used to measure Temperature, Candela is used to measure Intensity of flame, Steredian is used to measure Solid Angle.
[13] Which one of the following types of glass can cut off ultraviolet rays?
A.
Soda glass
B.
Pyrex glass
C.
Jena glass
D.
Crookes glass
Ans:
Crookes glass
Explanation :
In this glass mainly cerium oxide (CiO2) is present which sharply absorbs the ultraviolet rays from the sunlight so utilized in making lenses of eye glasses.
[14] Light year is a unit of –
A.
Light
B.
Current
C.
Distance
D.
Time
Ans:
Distance
Explanation :
A light-year is a unit of length used informally to express astronomical distances. It is equal to just under 10 trillion kilometres.
[15] The word 'insulation' means –
A.
matters which insulate
B.
incoming solar radiation
C.
insoluble matters
D.
None of the above
Ans:
incoming solar radiation
Explanation :
Insolation is the solar radiation that reaches the earth’s surface. It is measured by the amount of solar energy received per square centimeter per minute. Insolation affects temperature. The more the insolation, the higher is the temperature.
[16] Which of the following is not a vector quantity?
A.
Speed
B.
Velocity
C.
Torque
D.
Displacement
Ans:
Speed
Explanation :
Speed is a scalar quantity that refers to "how fast an object is moving." Speed can be thought of as the rate at which an object covers distance. It does not keep track of direction. In contrast, velocity is a vector quantity as it is direction aware.
[17] An object with a constant speed –
A.
is not accelerated
B.
might be accelerated
C.
is always accelerated
D.
also has a constant velocity
Ans:
is not accelerated
Explanation :
Acceleration is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. An object with constant speed will have no acceleration as the speed is uniform.
[18] The instrument used to regulate temperature to a particular degree is called :
A.
Thermostat
B.
Thermometer
C.
Pyrometer
D.
Thermocouple
Ans:
Thermostat
Explanation :
A thermostat is a component which senses the temperature of a system so that the system's temperature is maintained near a desired set point. At its core, a thermostat is simply the controls used to regulate temperature in a heating system.
[19] The power dissipated in a resistance is given by?
A.
V²/R
B.
IV
C.
All of these
D.
I²R
Ans:
All of these
Explanation :
Any resistor in a circuit that has a voltage drop across it dissipates electrical power. This electrical power is converted into heat energy hence all resistors have a power rating.
[20] The technique used by bats to find their way or to locate food is _.
A.
SONAR
B.
RADAR
C.
Echolocation
D.
Flapping
Ans:
Echolocation
Explanation :
Bats use echolocation to navigate and find food in the dark. To echolocate, bats send out sound waves from their mouth or nose. When the sound waves hit an object they produce echoes.
[21] In the absence of the earth's atmosphere, sky would appear –
A.
blue
B.
deep red
C.
white
D.
black
Ans:
black
Explanation :
Sky appears blue because the tiny particles of the earth's atmosphere scatter the blue colour (short wavelength) of the sunlight more dominantly than other wavelengths. A blue sky is a manifestation of Rayleigh scatter. The sky would appear black in the absence of earth's atmosphere because there would be no particles to scatter the light.
[22] If ice floating on water in a vessel melts, the water level in the vessel -
A.
increases
B.
does not change
C.
first increases before decreasing
D.
decreases
Ans:
does not change
Explanation :
When ice floating on water in a vessel melts, the water level in the vessel does not change. This is because when floating, the ice displaces an amount of water equal to its mass, and when melted, it becomes an amount of water equal to its mass. It is accordance with Archimedes Principle, which states that the mass of the liquid displaced by a floating object is equivalent to the mass of the object.
[23] One micron is equal to-
A.
1/10th of mm
B.
1/100th of mm
C.
1/1000th of mm
D.
1/10000th of mm
Ans:
1/1000th of mm
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
In this glass mainly cerium oxide (CiO2) is present which sharply absorbs the ultraviolet rays from the sunlight so utilized in making lenses of eye glasses.
[14] Light year is a unit of –
A.
Light
B.
Current
C.
Distance
D.
Time
Ans:
Distance
Explanation :
A light-year is a unit of length used informally to express astronomical distances. It is equal to just under 10 trillion kilometres.
[15] The word 'insulation' means –
A.
matters which insulate
B.
incoming solar radiation
C.
insoluble matters
D.
None of the above
Ans:
incoming solar radiation
Explanation :
Insolation is the solar radiation that reaches the earth’s surface. It is measured by the amount of solar energy received per square centimeter per minute. Insolation affects temperature. The more the insolation, the higher is the temperature.
[16] Which of the following is not a vector quantity?
A.
Speed
B.
Velocity
C.
Torque
D.
Displacement
Ans:
Speed
Explanation :
Speed is a scalar quantity that refers to "how fast an object is moving." Speed can be thought of as the rate at which an object covers distance. It does not keep track of direction. In contrast, velocity is a vector quantity as it is direction aware.
[17] An object with a constant speed –
A.
is not accelerated
B.
might be accelerated
C.
is always accelerated
D.
also has a constant velocity
Ans:
is not accelerated
Explanation :
Acceleration is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. An object with constant speed will have no acceleration as the speed is uniform.
[18] The instrument used to regulate temperature to a particular degree is called :
A.
Thermostat
B.
Thermometer
C.
Pyrometer
D.
Thermocouple
Ans:
Thermostat
Explanation :
A thermostat is a component which senses the temperature of a system so that the system's temperature is maintained near a desired set point. At its core, a thermostat is simply the controls used to regulate temperature in a heating system.
[19] The power dissipated in a resistance is given by?
A.
V²/R
B.
IV
C.
All of these
D.
I²R
Ans:
All of these
Explanation :
Any resistor in a circuit that has a voltage drop across it dissipates electrical power. This electrical power is converted into heat energy hence all resistors have a power rating.
[20] The technique used by bats to find their way or to locate food is _.
A.
SONAR
B.
RADAR
C.
Echolocation
D.
Flapping
Ans:
Echolocation
Explanation :
Bats use echolocation to navigate and find food in the dark. To echolocate, bats send out sound waves from their mouth or nose. When the sound waves hit an object they produce echoes.
[21] In the absence of the earth's atmosphere, sky would appear –
A.
blue
B.
deep red
C.
white
D.
black
Ans:
black
Explanation :
Sky appears blue because the tiny particles of the earth's atmosphere scatter the blue colour (short wavelength) of the sunlight more dominantly than other wavelengths. A blue sky is a manifestation of Rayleigh scatter. The sky would appear black in the absence of earth's atmosphere because there would be no particles to scatter the light.
[22] If ice floating on water in a vessel melts, the water level in the vessel -
A.
increases
B.
does not change
C.
first increases before decreasing
D.
decreases
Ans:
does not change
Explanation :
When ice floating on water in a vessel melts, the water level in the vessel does not change. This is because when floating, the ice displaces an amount of water equal to its mass, and when melted, it becomes an amount of water equal to its mass. It is accordance with Archimedes Principle, which states that the mass of the liquid displaced by a floating object is equivalent to the mass of the object.
[23] One micron is equal to-
A.
1/10th of mm
B.
1/100th of mm
C.
1/1000th of mm
D.
1/10000th of mm
Ans:
1/1000th of mm
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
Insolation is the solar radiation that reaches the earth’s surface. It is measured by the amount of solar energy received per square centimeter per minute. Insolation affects temperature. The more the insolation, the higher is the temperature.
[16] Which of the following is not a vector quantity?
A.
Speed
B.
Velocity
C.
Torque
D.
Displacement
Ans:
Speed
Explanation :
Speed is a scalar quantity that refers to "how fast an object is moving." Speed can be thought of as the rate at which an object covers distance. It does not keep track of direction. In contrast, velocity is a vector quantity as it is direction aware.
[17] An object with a constant speed –
A.
is not accelerated
B.
might be accelerated
C.
is always accelerated
D.
also has a constant velocity
Ans:
is not accelerated
Explanation :
Acceleration is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. An object with constant speed will have no acceleration as the speed is uniform.
[18] The instrument used to regulate temperature to a particular degree is called :
A.
Thermostat
B.
Thermometer
C.
Pyrometer
D.
Thermocouple
Ans:
Thermostat
Explanation :
A thermostat is a component which senses the temperature of a system so that the system's temperature is maintained near a desired set point. At its core, a thermostat is simply the controls used to regulate temperature in a heating system.
[19] The power dissipated in a resistance is given by?
A.
V²/R
B.
IV
C.
All of these
D.
I²R
Ans:
All of these
Explanation :
Any resistor in a circuit that has a voltage drop across it dissipates electrical power. This electrical power is converted into heat energy hence all resistors have a power rating.
[20] The technique used by bats to find their way or to locate food is _.
A.
SONAR
B.
RADAR
C.
Echolocation
D.
Flapping
Ans:
Echolocation
Explanation :
Bats use echolocation to navigate and find food in the dark. To echolocate, bats send out sound waves from their mouth or nose. When the sound waves hit an object they produce echoes.
[21] In the absence of the earth's atmosphere, sky would appear –
A.
blue
B.
deep red
C.
white
D.
black
Ans:
black
Explanation :
Sky appears blue because the tiny particles of the earth's atmosphere scatter the blue colour (short wavelength) of the sunlight more dominantly than other wavelengths. A blue sky is a manifestation of Rayleigh scatter. The sky would appear black in the absence of earth's atmosphere because there would be no particles to scatter the light.
[22] If ice floating on water in a vessel melts, the water level in the vessel -
A.
increases
B.
does not change
C.
first increases before decreasing
D.
decreases
Ans:
does not change
Explanation :
When ice floating on water in a vessel melts, the water level in the vessel does not change. This is because when floating, the ice displaces an amount of water equal to its mass, and when melted, it becomes an amount of water equal to its mass. It is accordance with Archimedes Principle, which states that the mass of the liquid displaced by a floating object is equivalent to the mass of the object.
[23] One micron is equal to-
A.
1/10th of mm
B.
1/100th of mm
C.
1/1000th of mm
D.
1/10000th of mm
Ans:
1/1000th of mm
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
Acceleration is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. An object with constant speed will have no acceleration as the speed is uniform.
[18] The instrument used to regulate temperature to a particular degree is called :
A.
Thermostat
B.
Thermometer
C.
Pyrometer
D.
Thermocouple
Ans:
Thermostat
Explanation :
A thermostat is a component which senses the temperature of a system so that the system's temperature is maintained near a desired set point. At its core, a thermostat is simply the controls used to regulate temperature in a heating system.
[19] The power dissipated in a resistance is given by?
A.
V²/R
B.
IV
C.
All of these
D.
I²R
Ans:
All of these
Explanation :
Any resistor in a circuit that has a voltage drop across it dissipates electrical power. This electrical power is converted into heat energy hence all resistors have a power rating.
[20] The technique used by bats to find their way or to locate food is _.
A.
SONAR
B.
RADAR
C.
Echolocation
D.
Flapping
Ans:
Echolocation
Explanation :
Bats use echolocation to navigate and find food in the dark. To echolocate, bats send out sound waves from their mouth or nose. When the sound waves hit an object they produce echoes.
[21] In the absence of the earth's atmosphere, sky would appear –
A.
blue
B.
deep red
C.
white
D.
black
Ans:
black
Explanation :
Sky appears blue because the tiny particles of the earth's atmosphere scatter the blue colour (short wavelength) of the sunlight more dominantly than other wavelengths. A blue sky is a manifestation of Rayleigh scatter. The sky would appear black in the absence of earth's atmosphere because there would be no particles to scatter the light.
[22] If ice floating on water in a vessel melts, the water level in the vessel -
A.
increases
B.
does not change
C.
first increases before decreasing
D.
decreases
Ans:
does not change
Explanation :
When ice floating on water in a vessel melts, the water level in the vessel does not change. This is because when floating, the ice displaces an amount of water equal to its mass, and when melted, it becomes an amount of water equal to its mass. It is accordance with Archimedes Principle, which states that the mass of the liquid displaced by a floating object is equivalent to the mass of the object.
[23] One micron is equal to-
A.
1/10th of mm
B.
1/100th of mm
C.
1/1000th of mm
D.
1/10000th of mm
Ans:
1/1000th of mm
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
Any resistor in a circuit that has a voltage drop across it dissipates electrical power. This electrical power is converted into heat energy hence all resistors have a power rating.
[20] The technique used by bats to find their way or to locate food is _.
A.
SONAR
B.
RADAR
C.
Echolocation
D.
Flapping
Ans:
Echolocation
Explanation :
Bats use echolocation to navigate and find food in the dark. To echolocate, bats send out sound waves from their mouth or nose. When the sound waves hit an object they produce echoes.
[21] In the absence of the earth's atmosphere, sky would appear –
A.
blue
B.
deep red
C.
white
D.
black
Ans:
black
Explanation :
Sky appears blue because the tiny particles of the earth's atmosphere scatter the blue colour (short wavelength) of the sunlight more dominantly than other wavelengths. A blue sky is a manifestation of Rayleigh scatter. The sky would appear black in the absence of earth's atmosphere because there would be no particles to scatter the light.
[22] If ice floating on water in a vessel melts, the water level in the vessel -
A.
increases
B.
does not change
C.
first increases before decreasing
D.
decreases
Ans:
does not change
Explanation :
When ice floating on water in a vessel melts, the water level in the vessel does not change. This is because when floating, the ice displaces an amount of water equal to its mass, and when melted, it becomes an amount of water equal to its mass. It is accordance with Archimedes Principle, which states that the mass of the liquid displaced by a floating object is equivalent to the mass of the object.
[23] One micron is equal to-
A.
1/10th of mm
B.
1/100th of mm
C.
1/1000th of mm
D.
1/10000th of mm
Ans:
1/1000th of mm
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
Sky appears blue because the tiny particles of the earth's atmosphere scatter the blue colour (short wavelength) of the sunlight more dominantly than other wavelengths. A blue sky is a manifestation of Rayleigh scatter. The sky would appear black in the absence of earth's atmosphere because there would be no particles to scatter the light.
[22] If ice floating on water in a vessel melts, the water level in the vessel -
A.
increases
B.
does not change
C.
first increases before decreasing
D.
decreases
Ans:
does not change
Explanation :
When ice floating on water in a vessel melts, the water level in the vessel does not change. This is because when floating, the ice displaces an amount of water equal to its mass, and when melted, it becomes an amount of water equal to its mass. It is accordance with Archimedes Principle, which states that the mass of the liquid displaced by a floating object is equivalent to the mass of the object.
[23] One micron is equal to-
A.
1/10th of mm
B.
1/100th of mm
C.
1/1000th of mm
D.
1/10000th of mm
Ans:
1/1000th of mm
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
In the U.S. the thickness of paint is expressed in mils (one mil equals 1/1000 of inch). The rest of the world expresses coating thickness in microns (1 micron = 1 millionth of a meter and 25.4 microns = .001” inch or 1 mil).
[24] Quality of a musical note depends on –
A.
Fundamental frequency
B.
Amplitude of the wave
C.
Harmonics present
D.
Velocity of sound in the medium
Ans:
Harmonics present
Explanation :
Sound "quality" or "timbre" describes those characteristics of sound which allow the ear to distinguish sounds which have the same pitch and loudness. Timbre is mainly determined by the harmonic content of a sound and the dynamic characteristics of the sound such as vibrato and the attack-decay envelope of the sound. Harmonic content is the most important of these.
[25] Silicon is used in which of the following?
A.
Semiconductors
B.
solar energy devices
C.
transistors
D.
All of these
Ans:
All of these
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.
Explanation :
Silicon is a chemical element (its symbol in chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14.