[1] Tape recorder should not be kept near one of the following things –
A.
Clock
B.
Magnet
C.
Electrical switchboard
D.
Radio
Ans:
Magnet
Explanation :
The cassette tape contains a magnetic strip wound around two spools. Tiny magnetic particles are randomly scattered throughout the tape. A tape recorder should not be kept near a magnet as the latter can cause the magnetic material to be pushed and pulled out of place. Rearranging the magnetic particles erases the sound.
[2] Which physical quantity is measured in ‘siemens’?
A.
Electric potential
B.
Electrical conductance
C.
Magnetic flux
D.
Refractive index
Ans:
Electrical conductance
Explanation :
The Siemens is the unit of electric conductance, electric susceptance and electric admittance in the International System of Units (SI).
[3] The surface tension of water on adding detergent to it –
A.
increases
B.
decreases
C.
no change
D.
becomes zero
Ans:
decreases
Explanation :
In the solid and liquid phase, water molecules are bonded to each other by virtue of an interaction between hydrogen atoms on one molecule and the oxygen atom of another — the process is referred to as "hydrogen bonding." The result is a kind of "skin" on liquid water's surface.
[4] In a refrigerator, the cooling system should always be –
A.
at the top
B.
at the bottom
C.
at the middle
D.
can be anywhere
Ans:
at the bottom
Explanation :
The compressor is the motor (or engine) of the cooling system. It is normally at the bottom of the refrigerator in the back. The compressor runs whenever the refrigerator thermostat calls for cooling.
[5] Which of the following is optical illusion?
A.
Rainbow
B.
Earthshine
C.
Halo
D.
Mirage
Ans:
Mirage
Explanation :
A mirage is a naturally occurring optical illusion or phenomenon in which light rays are bent due to refraction in layers of air of varying density. The image usually is upside down, enhancing the i llusion that the sky image seen in the distance is really a water or oil puddle acting as a mirror.
[6] 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.
[7] If the length of a simple pendulum is halved then its period of oscillation is -
A.
doubled
B.
halved
C.
increased by a factor √ 2
D.
decreased by a factor √ 2
Ans:
decreased by a factor √ 2
Explanation :
[8] Lux is the SI unit of -
A.
intensity of illumination
B.
luminous efficiency
C.
luminous flux
D.
luminous intensity
Ans:
intensity of illumination
Explanation :
The SI unit of intensity of illumination (illuminance) is the lux. An illuminance of 1.0 lux is produced by 1.0 lumen of light shining on an area of 1.0 m2.
[9] Eclipses occur due to which optical phenomena?
A.
Reflection
B.
Refraction
C.
Rectilinear propagation
D.
Diffraction
Ans:
Rectilinear propagation
Explanation :
An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer. Rectilinear propagation is a wave property which states that waves propagate (move or spread out) in straight lines.
[10] Pure water is bad conductor of electricity because it is –
A.
feebly ionized
B.
not volatile
C.
a very good solvent
D.
a non-polar solvent
Ans:
feebly ionized
Explanation :
Pure water is a covalent compound. It exists as simple discrete molecules and have a simple molecular structure. Hence, it does not exist as ions. Therefore, pure water cannot conduct electricity due to the absence of mobile ions and electrons. One instance that water can conduct electricity is when there are dissolved substance in it. Only then will water dissociate into hydrogen ions and hydroxide ions. The presence of mobile ions enables it to conduct electricity.
[11] Pycnometer is an instrument used to measure the –
A.
Density
B.
Intensity of solar radiation
C.
Intensity of earthquake
D.
High temperatures
Ans:
Density
Explanation :
A gas pycnometer is a laboratory device used for measuring the density — or more accurately the volume — of solids, be they regularly shaped, porous or non-porous, monolithic, powdered, granular or in some way comminuted, employing some method of has displacement and the volume-pressure relationship known as Boyle's Law.
[12] Lamberts law is related to –
A.
Reflection
B.
Refraction
C.
Interference
D.
Illumination
Ans:
Illumination
Explanation :
Lambert's Law says that the intensity of emitted light from a surface is directly proportional to the cosine of the angle between the line of view and the normal to the surface. A Lambertian surface is a surface that follows this rule exactly. In practice, most surfaces are not perfectly Lambertian. A surface which obeys Lambert's law is said to be Lambertian, and exhibits Lambertian reflectance. Such a surface has the same radiance when viewed from any angle.
[13] Rain drops acquire spherical shape due to -
A.
viscosity
B.
surface tension
C.
friction
D.
elasticity
Ans:
surface tension
Explanation :
The Surface tension pulls the surface of the drop equally at all points thus produces the spherical shape having the minimum surface area.
[14] The angular velocity depends upon the rate of change of the .
A.
Angular Distance
B.
Angular acceleration
C.
Angular Displacement
D.
torque
Ans:
Angular Displacement
Explanation :
The angular velocity is defined as the rate of change of angular displacement and is a vector quantity which specifies the angular speed of an object and the axis about which the object is rotating.
[15] Coolis tube is used to produce –
A.
Radio waves
B.
Micro waves
C.
X-rays
D.
Gama rays
Ans:
X-rays
Explanation :
X-rays are part of the electromagnetic spectrum, an ionizing radiation with wavelengths shorter than ultraviolet light. X-ray tubes evolved from experimental Crookes tubes with which X-rays were first discovered in the late 19th century, and the availability of this controllable source of X-rays created the field of radiography, the imaging of opaque objects with penetrating radiation.
[16] Which of the following is used for regulated electric supply?
A.
Zener diode
B.
Junction diode
C.
Gun diode
D.
Tunnel diode
Ans:
Zener diode
Explanation :
The Zener diode is like a general-purpose signal diode. When based in the forward direction it behaves just like a normal signal diode, but when a reverse voltage is applied to it, the voltage remains constant for a wide range of currents and hence widely used for regulated electric supply. The device was named after Clarence Zener, who discovered this electrical property. Many diodes described as “Zener” diodes rely instead on avalanche breakdown as the mechanism. Common applications include providing a reference voltage for voltage regulators, or to protect other semiconductor devices from momentary voltage pulses. Zener diodes are widely used as voltage references and as shunt regulators to regulate the voltage across small circuits.
[17] What is found in frequency modulation?
A.
Fixed frequency
B.
Fixed dimension
C.
Change in frequency and dimension
D.
Change in dimension only
Ans:
Fixed frequency
Explanation :
Frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant. Frequency modulation is also used in telemetry, radar, seismic prospecting and newborn EEG seizure monitoring.
[18] When the speed of car is doubled, then what will be the braking force of the car to stop it in the same distance?
A.
four times
B.
two times
C.
half
D.
one-fourth
Ans:
four times
Explanation :
Brake force, also known as Brake Power, is a measure of braking power of a vehicle. Suppose a car whose mass is 'x' and is braked from a speed of y km/hr to come to halt at a uniform retardation in z min. If the speed of the car is doubled in the same distance, then the braking force required to stop the car is four times the original speed i.e. '4v'. Note that all the parameters remain to be same.
[19] What is the maximum value of deforming force up to which a material shows elastic property and above which the material loses it?
A.
Elasticity
B.
Strain
C.
Elastic Limit
D.
Stress
Ans:
Stress
Explanation :
The Maximum Extent to which a solid may be stretched without permanent alteration of size or shape.
[20] The method of protecting iron from rusting, by coating a thin layer of Zinc is called -
A.
Galvanizing
B.
rancidity
C.
Alloy
D.
Pulverizing
Ans:
Galvanizing
Explanation :
Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting.
[21] Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by –
A.
Carbon dioxide
B.
Ammonia
C.
Chlorine
D.
Ozone
Ans:
Ozone
Explanation :
The ozone layer absorbs 97-99% of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Ozone is formed from di- oxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
[22] "Curie" is unit of :
A.
Radioactivity
B.
Temperature
C.
Heat
D.
Energy
Ans:
Radioactivity
Explanation :
Curie, in physics, unit of activity of a quantity of a radioactive substance, named in honour of the French physicist Marie Curie. One curie (1 Ci) is equal to 3.7 x 1010 Becquerel (Bq). Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.
[23] Speed of sound is the greatest in :
A.
Water
B.
Air
C.
Glass
D.
Glycerine
Ans:
Glass
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
The cassette tape contains a magnetic strip wound around two spools. Tiny magnetic particles are randomly scattered throughout the tape. A tape recorder should not be kept near a magnet as the latter can cause the magnetic material to be pushed and pulled out of place. Rearranging the magnetic particles erases the sound.
[2] Which physical quantity is measured in ‘siemens’?
A.
Electric potential
B.
Electrical conductance
C.
Magnetic flux
D.
Refractive index
Ans:
Electrical conductance
Explanation :
The Siemens is the unit of electric conductance, electric susceptance and electric admittance in the International System of Units (SI).
[3] The surface tension of water on adding detergent to it –
A.
increases
B.
decreases
C.
no change
D.
becomes zero
Ans:
decreases
Explanation :
In the solid and liquid phase, water molecules are bonded to each other by virtue of an interaction between hydrogen atoms on one molecule and the oxygen atom of another — the process is referred to as "hydrogen bonding." The result is a kind of "skin" on liquid water's surface.
[4] In a refrigerator, the cooling system should always be –
A.
at the top
B.
at the bottom
C.
at the middle
D.
can be anywhere
Ans:
at the bottom
Explanation :
The compressor is the motor (or engine) of the cooling system. It is normally at the bottom of the refrigerator in the back. The compressor runs whenever the refrigerator thermostat calls for cooling.
[5] Which of the following is optical illusion?
A.
Rainbow
B.
Earthshine
C.
Halo
D.
Mirage
Ans:
Mirage
Explanation :
A mirage is a naturally occurring optical illusion or phenomenon in which light rays are bent due to refraction in layers of air of varying density. The image usually is upside down, enhancing the i llusion that the sky image seen in the distance is really a water or oil puddle acting as a mirror.
[6] 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.
[7] If the length of a simple pendulum is halved then its period of oscillation is -
A.
doubled
B.
halved
C.
increased by a factor √ 2
D.
decreased by a factor √ 2
Ans:
decreased by a factor √ 2
Explanation :
[8] Lux is the SI unit of -
A.
intensity of illumination
B.
luminous efficiency
C.
luminous flux
D.
luminous intensity
Ans:
intensity of illumination
Explanation :
The SI unit of intensity of illumination (illuminance) is the lux. An illuminance of 1.0 lux is produced by 1.0 lumen of light shining on an area of 1.0 m2.
[9] Eclipses occur due to which optical phenomena?
A.
Reflection
B.
Refraction
C.
Rectilinear propagation
D.
Diffraction
Ans:
Rectilinear propagation
Explanation :
An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer. Rectilinear propagation is a wave property which states that waves propagate (move or spread out) in straight lines.
[10] Pure water is bad conductor of electricity because it is –
A.
feebly ionized
B.
not volatile
C.
a very good solvent
D.
a non-polar solvent
Ans:
feebly ionized
Explanation :
Pure water is a covalent compound. It exists as simple discrete molecules and have a simple molecular structure. Hence, it does not exist as ions. Therefore, pure water cannot conduct electricity due to the absence of mobile ions and electrons. One instance that water can conduct electricity is when there are dissolved substance in it. Only then will water dissociate into hydrogen ions and hydroxide ions. The presence of mobile ions enables it to conduct electricity.
[11] Pycnometer is an instrument used to measure the –
A.
Density
B.
Intensity of solar radiation
C.
Intensity of earthquake
D.
High temperatures
Ans:
Density
Explanation :
A gas pycnometer is a laboratory device used for measuring the density — or more accurately the volume — of solids, be they regularly shaped, porous or non-porous, monolithic, powdered, granular or in some way comminuted, employing some method of has displacement and the volume-pressure relationship known as Boyle's Law.
[12] Lamberts law is related to –
A.
Reflection
B.
Refraction
C.
Interference
D.
Illumination
Ans:
Illumination
Explanation :
Lambert's Law says that the intensity of emitted light from a surface is directly proportional to the cosine of the angle between the line of view and the normal to the surface. A Lambertian surface is a surface that follows this rule exactly. In practice, most surfaces are not perfectly Lambertian. A surface which obeys Lambert's law is said to be Lambertian, and exhibits Lambertian reflectance. Such a surface has the same radiance when viewed from any angle.
[13] Rain drops acquire spherical shape due to -
A.
viscosity
B.
surface tension
C.
friction
D.
elasticity
Ans:
surface tension
Explanation :
The Surface tension pulls the surface of the drop equally at all points thus produces the spherical shape having the minimum surface area.
[14] The angular velocity depends upon the rate of change of the .
A.
Angular Distance
B.
Angular acceleration
C.
Angular Displacement
D.
torque
Ans:
Angular Displacement
Explanation :
The angular velocity is defined as the rate of change of angular displacement and is a vector quantity which specifies the angular speed of an object and the axis about which the object is rotating.
[15] Coolis tube is used to produce –
A.
Radio waves
B.
Micro waves
C.
X-rays
D.
Gama rays
Ans:
X-rays
Explanation :
X-rays are part of the electromagnetic spectrum, an ionizing radiation with wavelengths shorter than ultraviolet light. X-ray tubes evolved from experimental Crookes tubes with which X-rays were first discovered in the late 19th century, and the availability of this controllable source of X-rays created the field of radiography, the imaging of opaque objects with penetrating radiation.
[16] Which of the following is used for regulated electric supply?
A.
Zener diode
B.
Junction diode
C.
Gun diode
D.
Tunnel diode
Ans:
Zener diode
Explanation :
The Zener diode is like a general-purpose signal diode. When based in the forward direction it behaves just like a normal signal diode, but when a reverse voltage is applied to it, the voltage remains constant for a wide range of currents and hence widely used for regulated electric supply. The device was named after Clarence Zener, who discovered this electrical property. Many diodes described as “Zener” diodes rely instead on avalanche breakdown as the mechanism. Common applications include providing a reference voltage for voltage regulators, or to protect other semiconductor devices from momentary voltage pulses. Zener diodes are widely used as voltage references and as shunt regulators to regulate the voltage across small circuits.
[17] What is found in frequency modulation?
A.
Fixed frequency
B.
Fixed dimension
C.
Change in frequency and dimension
D.
Change in dimension only
Ans:
Fixed frequency
Explanation :
Frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant. Frequency modulation is also used in telemetry, radar, seismic prospecting and newborn EEG seizure monitoring.
[18] When the speed of car is doubled, then what will be the braking force of the car to stop it in the same distance?
A.
four times
B.
two times
C.
half
D.
one-fourth
Ans:
four times
Explanation :
Brake force, also known as Brake Power, is a measure of braking power of a vehicle. Suppose a car whose mass is 'x' and is braked from a speed of y km/hr to come to halt at a uniform retardation in z min. If the speed of the car is doubled in the same distance, then the braking force required to stop the car is four times the original speed i.e. '4v'. Note that all the parameters remain to be same.
[19] What is the maximum value of deforming force up to which a material shows elastic property and above which the material loses it?
A.
Elasticity
B.
Strain
C.
Elastic Limit
D.
Stress
Ans:
Stress
Explanation :
The Maximum Extent to which a solid may be stretched without permanent alteration of size or shape.
[20] The method of protecting iron from rusting, by coating a thin layer of Zinc is called -
A.
Galvanizing
B.
rancidity
C.
Alloy
D.
Pulverizing
Ans:
Galvanizing
Explanation :
Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting.
[21] Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by –
A.
Carbon dioxide
B.
Ammonia
C.
Chlorine
D.
Ozone
Ans:
Ozone
Explanation :
The ozone layer absorbs 97-99% of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Ozone is formed from di- oxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
[22] "Curie" is unit of :
A.
Radioactivity
B.
Temperature
C.
Heat
D.
Energy
Ans:
Radioactivity
Explanation :
Curie, in physics, unit of activity of a quantity of a radioactive substance, named in honour of the French physicist Marie Curie. One curie (1 Ci) is equal to 3.7 x 1010 Becquerel (Bq). Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.
[23] Speed of sound is the greatest in :
A.
Water
B.
Air
C.
Glass
D.
Glycerine
Ans:
Glass
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
In the solid and liquid phase, water molecules are bonded to each other by virtue of an interaction between hydrogen atoms on one molecule and the oxygen atom of another — the process is referred to as "hydrogen bonding." The result is a kind of "skin" on liquid water's surface.
[4] In a refrigerator, the cooling system should always be –
A.
at the top
B.
at the bottom
C.
at the middle
D.
can be anywhere
Ans:
at the bottom
Explanation :
The compressor is the motor (or engine) of the cooling system. It is normally at the bottom of the refrigerator in the back. The compressor runs whenever the refrigerator thermostat calls for cooling.
[5] Which of the following is optical illusion?
A.
Rainbow
B.
Earthshine
C.
Halo
D.
Mirage
Ans:
Mirage
Explanation :
A mirage is a naturally occurring optical illusion or phenomenon in which light rays are bent due to refraction in layers of air of varying density. The image usually is upside down, enhancing the i llusion that the sky image seen in the distance is really a water or oil puddle acting as a mirror.
[6] 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.
[7] If the length of a simple pendulum is halved then its period of oscillation is -
A.
doubled
B.
halved
C.
increased by a factor √ 2
D.
decreased by a factor √ 2
Ans:
decreased by a factor √ 2
Explanation :
[8] Lux is the SI unit of -
A.
intensity of illumination
B.
luminous efficiency
C.
luminous flux
D.
luminous intensity
Ans:
intensity of illumination
Explanation :
The SI unit of intensity of illumination (illuminance) is the lux. An illuminance of 1.0 lux is produced by 1.0 lumen of light shining on an area of 1.0 m2.
[9] Eclipses occur due to which optical phenomena?
A.
Reflection
B.
Refraction
C.
Rectilinear propagation
D.
Diffraction
Ans:
Rectilinear propagation
Explanation :
An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer. Rectilinear propagation is a wave property which states that waves propagate (move or spread out) in straight lines.
[10] Pure water is bad conductor of electricity because it is –
A.
feebly ionized
B.
not volatile
C.
a very good solvent
D.
a non-polar solvent
Ans:
feebly ionized
Explanation :
Pure water is a covalent compound. It exists as simple discrete molecules and have a simple molecular structure. Hence, it does not exist as ions. Therefore, pure water cannot conduct electricity due to the absence of mobile ions and electrons. One instance that water can conduct electricity is when there are dissolved substance in it. Only then will water dissociate into hydrogen ions and hydroxide ions. The presence of mobile ions enables it to conduct electricity.
[11] Pycnometer is an instrument used to measure the –
A.
Density
B.
Intensity of solar radiation
C.
Intensity of earthquake
D.
High temperatures
Ans:
Density
Explanation :
A gas pycnometer is a laboratory device used for measuring the density — or more accurately the volume — of solids, be they regularly shaped, porous or non-porous, monolithic, powdered, granular or in some way comminuted, employing some method of has displacement and the volume-pressure relationship known as Boyle's Law.
[12] Lamberts law is related to –
A.
Reflection
B.
Refraction
C.
Interference
D.
Illumination
Ans:
Illumination
Explanation :
Lambert's Law says that the intensity of emitted light from a surface is directly proportional to the cosine of the angle between the line of view and the normal to the surface. A Lambertian surface is a surface that follows this rule exactly. In practice, most surfaces are not perfectly Lambertian. A surface which obeys Lambert's law is said to be Lambertian, and exhibits Lambertian reflectance. Such a surface has the same radiance when viewed from any angle.
[13] Rain drops acquire spherical shape due to -
A.
viscosity
B.
surface tension
C.
friction
D.
elasticity
Ans:
surface tension
Explanation :
The Surface tension pulls the surface of the drop equally at all points thus produces the spherical shape having the minimum surface area.
[14] The angular velocity depends upon the rate of change of the .
A.
Angular Distance
B.
Angular acceleration
C.
Angular Displacement
D.
torque
Ans:
Angular Displacement
Explanation :
The angular velocity is defined as the rate of change of angular displacement and is a vector quantity which specifies the angular speed of an object and the axis about which the object is rotating.
[15] Coolis tube is used to produce –
A.
Radio waves
B.
Micro waves
C.
X-rays
D.
Gama rays
Ans:
X-rays
Explanation :
X-rays are part of the electromagnetic spectrum, an ionizing radiation with wavelengths shorter than ultraviolet light. X-ray tubes evolved from experimental Crookes tubes with which X-rays were first discovered in the late 19th century, and the availability of this controllable source of X-rays created the field of radiography, the imaging of opaque objects with penetrating radiation.
[16] Which of the following is used for regulated electric supply?
A.
Zener diode
B.
Junction diode
C.
Gun diode
D.
Tunnel diode
Ans:
Zener diode
Explanation :
The Zener diode is like a general-purpose signal diode. When based in the forward direction it behaves just like a normal signal diode, but when a reverse voltage is applied to it, the voltage remains constant for a wide range of currents and hence widely used for regulated electric supply. The device was named after Clarence Zener, who discovered this electrical property. Many diodes described as “Zener” diodes rely instead on avalanche breakdown as the mechanism. Common applications include providing a reference voltage for voltage regulators, or to protect other semiconductor devices from momentary voltage pulses. Zener diodes are widely used as voltage references and as shunt regulators to regulate the voltage across small circuits.
[17] What is found in frequency modulation?
A.
Fixed frequency
B.
Fixed dimension
C.
Change in frequency and dimension
D.
Change in dimension only
Ans:
Fixed frequency
Explanation :
Frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant. Frequency modulation is also used in telemetry, radar, seismic prospecting and newborn EEG seizure monitoring.
[18] When the speed of car is doubled, then what will be the braking force of the car to stop it in the same distance?
A.
four times
B.
two times
C.
half
D.
one-fourth
Ans:
four times
Explanation :
Brake force, also known as Brake Power, is a measure of braking power of a vehicle. Suppose a car whose mass is 'x' and is braked from a speed of y km/hr to come to halt at a uniform retardation in z min. If the speed of the car is doubled in the same distance, then the braking force required to stop the car is four times the original speed i.e. '4v'. Note that all the parameters remain to be same.
[19] What is the maximum value of deforming force up to which a material shows elastic property and above which the material loses it?
A.
Elasticity
B.
Strain
C.
Elastic Limit
D.
Stress
Ans:
Stress
Explanation :
The Maximum Extent to which a solid may be stretched without permanent alteration of size or shape.
[20] The method of protecting iron from rusting, by coating a thin layer of Zinc is called -
A.
Galvanizing
B.
rancidity
C.
Alloy
D.
Pulverizing
Ans:
Galvanizing
Explanation :
Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting.
[21] Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by –
A.
Carbon dioxide
B.
Ammonia
C.
Chlorine
D.
Ozone
Ans:
Ozone
Explanation :
The ozone layer absorbs 97-99% of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Ozone is formed from di- oxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
[22] "Curie" is unit of :
A.
Radioactivity
B.
Temperature
C.
Heat
D.
Energy
Ans:
Radioactivity
Explanation :
Curie, in physics, unit of activity of a quantity of a radioactive substance, named in honour of the French physicist Marie Curie. One curie (1 Ci) is equal to 3.7 x 1010 Becquerel (Bq). Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.
[23] Speed of sound is the greatest in :
A.
Water
B.
Air
C.
Glass
D.
Glycerine
Ans:
Glass
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
A mirage is a naturally occurring optical illusion or phenomenon in which light rays are bent due to refraction in layers of air of varying density. The image usually is upside down, enhancing the i llusion that the sky image seen in the distance is really a water or oil puddle acting as a mirror.
[6] 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.
[7] If the length of a simple pendulum is halved then its period of oscillation is -
A.
doubled
B.
halved
C.
increased by a factor √ 2
D.
decreased by a factor √ 2
Ans:
decreased by a factor √ 2
Explanation :
[8] Lux is the SI unit of -
A.
intensity of illumination
B.
luminous efficiency
C.
luminous flux
D.
luminous intensity
Ans:
intensity of illumination
Explanation :
The SI unit of intensity of illumination (illuminance) is the lux. An illuminance of 1.0 lux is produced by 1.0 lumen of light shining on an area of 1.0 m2.
[9] Eclipses occur due to which optical phenomena?
A.
Reflection
B.
Refraction
C.
Rectilinear propagation
D.
Diffraction
Ans:
Rectilinear propagation
Explanation :
An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer. Rectilinear propagation is a wave property which states that waves propagate (move or spread out) in straight lines.
[10] Pure water is bad conductor of electricity because it is –
A.
feebly ionized
B.
not volatile
C.
a very good solvent
D.
a non-polar solvent
Ans:
feebly ionized
Explanation :
Pure water is a covalent compound. It exists as simple discrete molecules and have a simple molecular structure. Hence, it does not exist as ions. Therefore, pure water cannot conduct electricity due to the absence of mobile ions and electrons. One instance that water can conduct electricity is when there are dissolved substance in it. Only then will water dissociate into hydrogen ions and hydroxide ions. The presence of mobile ions enables it to conduct electricity.
[11] Pycnometer is an instrument used to measure the –
A.
Density
B.
Intensity of solar radiation
C.
Intensity of earthquake
D.
High temperatures
Ans:
Density
Explanation :
A gas pycnometer is a laboratory device used for measuring the density — or more accurately the volume — of solids, be they regularly shaped, porous or non-porous, monolithic, powdered, granular or in some way comminuted, employing some method of has displacement and the volume-pressure relationship known as Boyle's Law.
[12] Lamberts law is related to –
A.
Reflection
B.
Refraction
C.
Interference
D.
Illumination
Ans:
Illumination
Explanation :
Lambert's Law says that the intensity of emitted light from a surface is directly proportional to the cosine of the angle between the line of view and the normal to the surface. A Lambertian surface is a surface that follows this rule exactly. In practice, most surfaces are not perfectly Lambertian. A surface which obeys Lambert's law is said to be Lambertian, and exhibits Lambertian reflectance. Such a surface has the same radiance when viewed from any angle.
[13] Rain drops acquire spherical shape due to -
A.
viscosity
B.
surface tension
C.
friction
D.
elasticity
Ans:
surface tension
Explanation :
The Surface tension pulls the surface of the drop equally at all points thus produces the spherical shape having the minimum surface area.
[14] The angular velocity depends upon the rate of change of the .
A.
Angular Distance
B.
Angular acceleration
C.
Angular Displacement
D.
torque
Ans:
Angular Displacement
Explanation :
The angular velocity is defined as the rate of change of angular displacement and is a vector quantity which specifies the angular speed of an object and the axis about which the object is rotating.
[15] Coolis tube is used to produce –
A.
Radio waves
B.
Micro waves
C.
X-rays
D.
Gama rays
Ans:
X-rays
Explanation :
X-rays are part of the electromagnetic spectrum, an ionizing radiation with wavelengths shorter than ultraviolet light. X-ray tubes evolved from experimental Crookes tubes with which X-rays were first discovered in the late 19th century, and the availability of this controllable source of X-rays created the field of radiography, the imaging of opaque objects with penetrating radiation.
[16] Which of the following is used for regulated electric supply?
A.
Zener diode
B.
Junction diode
C.
Gun diode
D.
Tunnel diode
Ans:
Zener diode
Explanation :
The Zener diode is like a general-purpose signal diode. When based in the forward direction it behaves just like a normal signal diode, but when a reverse voltage is applied to it, the voltage remains constant for a wide range of currents and hence widely used for regulated electric supply. The device was named after Clarence Zener, who discovered this electrical property. Many diodes described as “Zener” diodes rely instead on avalanche breakdown as the mechanism. Common applications include providing a reference voltage for voltage regulators, or to protect other semiconductor devices from momentary voltage pulses. Zener diodes are widely used as voltage references and as shunt regulators to regulate the voltage across small circuits.
[17] What is found in frequency modulation?
A.
Fixed frequency
B.
Fixed dimension
C.
Change in frequency and dimension
D.
Change in dimension only
Ans:
Fixed frequency
Explanation :
Frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant. Frequency modulation is also used in telemetry, radar, seismic prospecting and newborn EEG seizure monitoring.
[18] When the speed of car is doubled, then what will be the braking force of the car to stop it in the same distance?
A.
four times
B.
two times
C.
half
D.
one-fourth
Ans:
four times
Explanation :
Brake force, also known as Brake Power, is a measure of braking power of a vehicle. Suppose a car whose mass is 'x' and is braked from a speed of y km/hr to come to halt at a uniform retardation in z min. If the speed of the car is doubled in the same distance, then the braking force required to stop the car is four times the original speed i.e. '4v'. Note that all the parameters remain to be same.
[19] What is the maximum value of deforming force up to which a material shows elastic property and above which the material loses it?
A.
Elasticity
B.
Strain
C.
Elastic Limit
D.
Stress
Ans:
Stress
Explanation :
The Maximum Extent to which a solid may be stretched without permanent alteration of size or shape.
[20] The method of protecting iron from rusting, by coating a thin layer of Zinc is called -
A.
Galvanizing
B.
rancidity
C.
Alloy
D.
Pulverizing
Ans:
Galvanizing
Explanation :
Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting.
[21] Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by –
A.
Carbon dioxide
B.
Ammonia
C.
Chlorine
D.
Ozone
Ans:
Ozone
Explanation :
The ozone layer absorbs 97-99% of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Ozone is formed from di- oxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
[22] "Curie" is unit of :
A.
Radioactivity
B.
Temperature
C.
Heat
D.
Energy
Ans:
Radioactivity
Explanation :
Curie, in physics, unit of activity of a quantity of a radioactive substance, named in honour of the French physicist Marie Curie. One curie (1 Ci) is equal to 3.7 x 1010 Becquerel (Bq). Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.
[23] Speed of sound is the greatest in :
A.
Water
B.
Air
C.
Glass
D.
Glycerine
Ans:
Glass
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
[8] Lux is the SI unit of -
A.
intensity of illumination
B.
luminous efficiency
C.
luminous flux
D.
luminous intensity
Ans:
intensity of illumination
Explanation :
The SI unit of intensity of illumination (illuminance) is the lux. An illuminance of 1.0 lux is produced by 1.0 lumen of light shining on an area of 1.0 m2.
[9] Eclipses occur due to which optical phenomena?
A.
Reflection
B.
Refraction
C.
Rectilinear propagation
D.
Diffraction
Ans:
Rectilinear propagation
Explanation :
An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer. Rectilinear propagation is a wave property which states that waves propagate (move or spread out) in straight lines.
[10] Pure water is bad conductor of electricity because it is –
A.
feebly ionized
B.
not volatile
C.
a very good solvent
D.
a non-polar solvent
Ans:
feebly ionized
Explanation :
Pure water is a covalent compound. It exists as simple discrete molecules and have a simple molecular structure. Hence, it does not exist as ions. Therefore, pure water cannot conduct electricity due to the absence of mobile ions and electrons. One instance that water can conduct electricity is when there are dissolved substance in it. Only then will water dissociate into hydrogen ions and hydroxide ions. The presence of mobile ions enables it to conduct electricity.
[11] Pycnometer is an instrument used to measure the –
A.
Density
B.
Intensity of solar radiation
C.
Intensity of earthquake
D.
High temperatures
Ans:
Density
Explanation :
A gas pycnometer is a laboratory device used for measuring the density — or more accurately the volume — of solids, be they regularly shaped, porous or non-porous, monolithic, powdered, granular or in some way comminuted, employing some method of has displacement and the volume-pressure relationship known as Boyle's Law.
[12] Lamberts law is related to –
A.
Reflection
B.
Refraction
C.
Interference
D.
Illumination
Ans:
Illumination
Explanation :
Lambert's Law says that the intensity of emitted light from a surface is directly proportional to the cosine of the angle between the line of view and the normal to the surface. A Lambertian surface is a surface that follows this rule exactly. In practice, most surfaces are not perfectly Lambertian. A surface which obeys Lambert's law is said to be Lambertian, and exhibits Lambertian reflectance. Such a surface has the same radiance when viewed from any angle.
[13] Rain drops acquire spherical shape due to -
A.
viscosity
B.
surface tension
C.
friction
D.
elasticity
Ans:
surface tension
Explanation :
The Surface tension pulls the surface of the drop equally at all points thus produces the spherical shape having the minimum surface area.
[14] The angular velocity depends upon the rate of change of the .
A.
Angular Distance
B.
Angular acceleration
C.
Angular Displacement
D.
torque
Ans:
Angular Displacement
Explanation :
The angular velocity is defined as the rate of change of angular displacement and is a vector quantity which specifies the angular speed of an object and the axis about which the object is rotating.
[15] Coolis tube is used to produce –
A.
Radio waves
B.
Micro waves
C.
X-rays
D.
Gama rays
Ans:
X-rays
Explanation :
X-rays are part of the electromagnetic spectrum, an ionizing radiation with wavelengths shorter than ultraviolet light. X-ray tubes evolved from experimental Crookes tubes with which X-rays were first discovered in the late 19th century, and the availability of this controllable source of X-rays created the field of radiography, the imaging of opaque objects with penetrating radiation.
[16] Which of the following is used for regulated electric supply?
A.
Zener diode
B.
Junction diode
C.
Gun diode
D.
Tunnel diode
Ans:
Zener diode
Explanation :
The Zener diode is like a general-purpose signal diode. When based in the forward direction it behaves just like a normal signal diode, but when a reverse voltage is applied to it, the voltage remains constant for a wide range of currents and hence widely used for regulated electric supply. The device was named after Clarence Zener, who discovered this electrical property. Many diodes described as “Zener” diodes rely instead on avalanche breakdown as the mechanism. Common applications include providing a reference voltage for voltage regulators, or to protect other semiconductor devices from momentary voltage pulses. Zener diodes are widely used as voltage references and as shunt regulators to regulate the voltage across small circuits.
[17] What is found in frequency modulation?
A.
Fixed frequency
B.
Fixed dimension
C.
Change in frequency and dimension
D.
Change in dimension only
Ans:
Fixed frequency
Explanation :
Frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant. Frequency modulation is also used in telemetry, radar, seismic prospecting and newborn EEG seizure monitoring.
[18] When the speed of car is doubled, then what will be the braking force of the car to stop it in the same distance?
A.
four times
B.
two times
C.
half
D.
one-fourth
Ans:
four times
Explanation :
Brake force, also known as Brake Power, is a measure of braking power of a vehicle. Suppose a car whose mass is 'x' and is braked from a speed of y km/hr to come to halt at a uniform retardation in z min. If the speed of the car is doubled in the same distance, then the braking force required to stop the car is four times the original speed i.e. '4v'. Note that all the parameters remain to be same.
[19] What is the maximum value of deforming force up to which a material shows elastic property and above which the material loses it?
A.
Elasticity
B.
Strain
C.
Elastic Limit
D.
Stress
Ans:
Stress
Explanation :
The Maximum Extent to which a solid may be stretched without permanent alteration of size or shape.
[20] The method of protecting iron from rusting, by coating a thin layer of Zinc is called -
A.
Galvanizing
B.
rancidity
C.
Alloy
D.
Pulverizing
Ans:
Galvanizing
Explanation :
Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting.
[21] Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by –
A.
Carbon dioxide
B.
Ammonia
C.
Chlorine
D.
Ozone
Ans:
Ozone
Explanation :
The ozone layer absorbs 97-99% of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Ozone is formed from di- oxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
[22] "Curie" is unit of :
A.
Radioactivity
B.
Temperature
C.
Heat
D.
Energy
Ans:
Radioactivity
Explanation :
Curie, in physics, unit of activity of a quantity of a radioactive substance, named in honour of the French physicist Marie Curie. One curie (1 Ci) is equal to 3.7 x 1010 Becquerel (Bq). Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.
[23] Speed of sound is the greatest in :
A.
Water
B.
Air
C.
Glass
D.
Glycerine
Ans:
Glass
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer. Rectilinear propagation is a wave property which states that waves propagate (move or spread out) in straight lines.
[10] Pure water is bad conductor of electricity because it is –
A.
feebly ionized
B.
not volatile
C.
a very good solvent
D.
a non-polar solvent
Ans:
feebly ionized
Explanation :
Pure water is a covalent compound. It exists as simple discrete molecules and have a simple molecular structure. Hence, it does not exist as ions. Therefore, pure water cannot conduct electricity due to the absence of mobile ions and electrons. One instance that water can conduct electricity is when there are dissolved substance in it. Only then will water dissociate into hydrogen ions and hydroxide ions. The presence of mobile ions enables it to conduct electricity.
[11] Pycnometer is an instrument used to measure the –
A.
Density
B.
Intensity of solar radiation
C.
Intensity of earthquake
D.
High temperatures
Ans:
Density
Explanation :
A gas pycnometer is a laboratory device used for measuring the density — or more accurately the volume — of solids, be they regularly shaped, porous or non-porous, monolithic, powdered, granular or in some way comminuted, employing some method of has displacement and the volume-pressure relationship known as Boyle's Law.
[12] Lamberts law is related to –
A.
Reflection
B.
Refraction
C.
Interference
D.
Illumination
Ans:
Illumination
Explanation :
Lambert's Law says that the intensity of emitted light from a surface is directly proportional to the cosine of the angle between the line of view and the normal to the surface. A Lambertian surface is a surface that follows this rule exactly. In practice, most surfaces are not perfectly Lambertian. A surface which obeys Lambert's law is said to be Lambertian, and exhibits Lambertian reflectance. Such a surface has the same radiance when viewed from any angle.
[13] Rain drops acquire spherical shape due to -
A.
viscosity
B.
surface tension
C.
friction
D.
elasticity
Ans:
surface tension
Explanation :
The Surface tension pulls the surface of the drop equally at all points thus produces the spherical shape having the minimum surface area.
[14] The angular velocity depends upon the rate of change of the .
A.
Angular Distance
B.
Angular acceleration
C.
Angular Displacement
D.
torque
Ans:
Angular Displacement
Explanation :
The angular velocity is defined as the rate of change of angular displacement and is a vector quantity which specifies the angular speed of an object and the axis about which the object is rotating.
[15] Coolis tube is used to produce –
A.
Radio waves
B.
Micro waves
C.
X-rays
D.
Gama rays
Ans:
X-rays
Explanation :
X-rays are part of the electromagnetic spectrum, an ionizing radiation with wavelengths shorter than ultraviolet light. X-ray tubes evolved from experimental Crookes tubes with which X-rays were first discovered in the late 19th century, and the availability of this controllable source of X-rays created the field of radiography, the imaging of opaque objects with penetrating radiation.
[16] Which of the following is used for regulated electric supply?
A.
Zener diode
B.
Junction diode
C.
Gun diode
D.
Tunnel diode
Ans:
Zener diode
Explanation :
The Zener diode is like a general-purpose signal diode. When based in the forward direction it behaves just like a normal signal diode, but when a reverse voltage is applied to it, the voltage remains constant for a wide range of currents and hence widely used for regulated electric supply. The device was named after Clarence Zener, who discovered this electrical property. Many diodes described as “Zener” diodes rely instead on avalanche breakdown as the mechanism. Common applications include providing a reference voltage for voltage regulators, or to protect other semiconductor devices from momentary voltage pulses. Zener diodes are widely used as voltage references and as shunt regulators to regulate the voltage across small circuits.
[17] What is found in frequency modulation?
A.
Fixed frequency
B.
Fixed dimension
C.
Change in frequency and dimension
D.
Change in dimension only
Ans:
Fixed frequency
Explanation :
Frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant. Frequency modulation is also used in telemetry, radar, seismic prospecting and newborn EEG seizure monitoring.
[18] When the speed of car is doubled, then what will be the braking force of the car to stop it in the same distance?
A.
four times
B.
two times
C.
half
D.
one-fourth
Ans:
four times
Explanation :
Brake force, also known as Brake Power, is a measure of braking power of a vehicle. Suppose a car whose mass is 'x' and is braked from a speed of y km/hr to come to halt at a uniform retardation in z min. If the speed of the car is doubled in the same distance, then the braking force required to stop the car is four times the original speed i.e. '4v'. Note that all the parameters remain to be same.
[19] What is the maximum value of deforming force up to which a material shows elastic property and above which the material loses it?
A.
Elasticity
B.
Strain
C.
Elastic Limit
D.
Stress
Ans:
Stress
Explanation :
The Maximum Extent to which a solid may be stretched without permanent alteration of size or shape.
[20] The method of protecting iron from rusting, by coating a thin layer of Zinc is called -
A.
Galvanizing
B.
rancidity
C.
Alloy
D.
Pulverizing
Ans:
Galvanizing
Explanation :
Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting.
[21] Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by –
A.
Carbon dioxide
B.
Ammonia
C.
Chlorine
D.
Ozone
Ans:
Ozone
Explanation :
The ozone layer absorbs 97-99% of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Ozone is formed from di- oxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
[22] "Curie" is unit of :
A.
Radioactivity
B.
Temperature
C.
Heat
D.
Energy
Ans:
Radioactivity
Explanation :
Curie, in physics, unit of activity of a quantity of a radioactive substance, named in honour of the French physicist Marie Curie. One curie (1 Ci) is equal to 3.7 x 1010 Becquerel (Bq). Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.
[23] Speed of sound is the greatest in :
A.
Water
B.
Air
C.
Glass
D.
Glycerine
Ans:
Glass
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
A gas pycnometer is a laboratory device used for measuring the density — or more accurately the volume — of solids, be they regularly shaped, porous or non-porous, monolithic, powdered, granular or in some way comminuted, employing some method of has displacement and the volume-pressure relationship known as Boyle's Law.
[12] Lamberts law is related to –
A.
Reflection
B.
Refraction
C.
Interference
D.
Illumination
Ans:
Illumination
Explanation :
Lambert's Law says that the intensity of emitted light from a surface is directly proportional to the cosine of the angle between the line of view and the normal to the surface. A Lambertian surface is a surface that follows this rule exactly. In practice, most surfaces are not perfectly Lambertian. A surface which obeys Lambert's law is said to be Lambertian, and exhibits Lambertian reflectance. Such a surface has the same radiance when viewed from any angle.
[13] Rain drops acquire spherical shape due to -
A.
viscosity
B.
surface tension
C.
friction
D.
elasticity
Ans:
surface tension
Explanation :
The Surface tension pulls the surface of the drop equally at all points thus produces the spherical shape having the minimum surface area.
[14] The angular velocity depends upon the rate of change of the .
A.
Angular Distance
B.
Angular acceleration
C.
Angular Displacement
D.
torque
Ans:
Angular Displacement
Explanation :
The angular velocity is defined as the rate of change of angular displacement and is a vector quantity which specifies the angular speed of an object and the axis about which the object is rotating.
[15] Coolis tube is used to produce –
A.
Radio waves
B.
Micro waves
C.
X-rays
D.
Gama rays
Ans:
X-rays
Explanation :
X-rays are part of the electromagnetic spectrum, an ionizing radiation with wavelengths shorter than ultraviolet light. X-ray tubes evolved from experimental Crookes tubes with which X-rays were first discovered in the late 19th century, and the availability of this controllable source of X-rays created the field of radiography, the imaging of opaque objects with penetrating radiation.
[16] Which of the following is used for regulated electric supply?
A.
Zener diode
B.
Junction diode
C.
Gun diode
D.
Tunnel diode
Ans:
Zener diode
Explanation :
The Zener diode is like a general-purpose signal diode. When based in the forward direction it behaves just like a normal signal diode, but when a reverse voltage is applied to it, the voltage remains constant for a wide range of currents and hence widely used for regulated electric supply. The device was named after Clarence Zener, who discovered this electrical property. Many diodes described as “Zener” diodes rely instead on avalanche breakdown as the mechanism. Common applications include providing a reference voltage for voltage regulators, or to protect other semiconductor devices from momentary voltage pulses. Zener diodes are widely used as voltage references and as shunt regulators to regulate the voltage across small circuits.
[17] What is found in frequency modulation?
A.
Fixed frequency
B.
Fixed dimension
C.
Change in frequency and dimension
D.
Change in dimension only
Ans:
Fixed frequency
Explanation :
Frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant. Frequency modulation is also used in telemetry, radar, seismic prospecting and newborn EEG seizure monitoring.
[18] When the speed of car is doubled, then what will be the braking force of the car to stop it in the same distance?
A.
four times
B.
two times
C.
half
D.
one-fourth
Ans:
four times
Explanation :
Brake force, also known as Brake Power, is a measure of braking power of a vehicle. Suppose a car whose mass is 'x' and is braked from a speed of y km/hr to come to halt at a uniform retardation in z min. If the speed of the car is doubled in the same distance, then the braking force required to stop the car is four times the original speed i.e. '4v'. Note that all the parameters remain to be same.
[19] What is the maximum value of deforming force up to which a material shows elastic property and above which the material loses it?
A.
Elasticity
B.
Strain
C.
Elastic Limit
D.
Stress
Ans:
Stress
Explanation :
The Maximum Extent to which a solid may be stretched without permanent alteration of size or shape.
[20] The method of protecting iron from rusting, by coating a thin layer of Zinc is called -
A.
Galvanizing
B.
rancidity
C.
Alloy
D.
Pulverizing
Ans:
Galvanizing
Explanation :
Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting.
[21] Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by –
A.
Carbon dioxide
B.
Ammonia
C.
Chlorine
D.
Ozone
Ans:
Ozone
Explanation :
The ozone layer absorbs 97-99% of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Ozone is formed from di- oxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
[22] "Curie" is unit of :
A.
Radioactivity
B.
Temperature
C.
Heat
D.
Energy
Ans:
Radioactivity
Explanation :
Curie, in physics, unit of activity of a quantity of a radioactive substance, named in honour of the French physicist Marie Curie. One curie (1 Ci) is equal to 3.7 x 1010 Becquerel (Bq). Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.
[23] Speed of sound is the greatest in :
A.
Water
B.
Air
C.
Glass
D.
Glycerine
Ans:
Glass
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
The Surface tension pulls the surface of the drop equally at all points thus produces the spherical shape having the minimum surface area.
[14] The angular velocity depends upon the rate of change of the .
A.
Angular Distance
B.
Angular acceleration
C.
Angular Displacement
D.
torque
Ans:
Angular Displacement
Explanation :
The angular velocity is defined as the rate of change of angular displacement and is a vector quantity which specifies the angular speed of an object and the axis about which the object is rotating.
[15] Coolis tube is used to produce –
A.
Radio waves
B.
Micro waves
C.
X-rays
D.
Gama rays
Ans:
X-rays
Explanation :
X-rays are part of the electromagnetic spectrum, an ionizing radiation with wavelengths shorter than ultraviolet light. X-ray tubes evolved from experimental Crookes tubes with which X-rays were first discovered in the late 19th century, and the availability of this controllable source of X-rays created the field of radiography, the imaging of opaque objects with penetrating radiation.
[16] Which of the following is used for regulated electric supply?
A.
Zener diode
B.
Junction diode
C.
Gun diode
D.
Tunnel diode
Ans:
Zener diode
Explanation :
The Zener diode is like a general-purpose signal diode. When based in the forward direction it behaves just like a normal signal diode, but when a reverse voltage is applied to it, the voltage remains constant for a wide range of currents and hence widely used for regulated electric supply. The device was named after Clarence Zener, who discovered this electrical property. Many diodes described as “Zener” diodes rely instead on avalanche breakdown as the mechanism. Common applications include providing a reference voltage for voltage regulators, or to protect other semiconductor devices from momentary voltage pulses. Zener diodes are widely used as voltage references and as shunt regulators to regulate the voltage across small circuits.
[17] What is found in frequency modulation?
A.
Fixed frequency
B.
Fixed dimension
C.
Change in frequency and dimension
D.
Change in dimension only
Ans:
Fixed frequency
Explanation :
Frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant. Frequency modulation is also used in telemetry, radar, seismic prospecting and newborn EEG seizure monitoring.
[18] When the speed of car is doubled, then what will be the braking force of the car to stop it in the same distance?
A.
four times
B.
two times
C.
half
D.
one-fourth
Ans:
four times
Explanation :
Brake force, also known as Brake Power, is a measure of braking power of a vehicle. Suppose a car whose mass is 'x' and is braked from a speed of y km/hr to come to halt at a uniform retardation in z min. If the speed of the car is doubled in the same distance, then the braking force required to stop the car is four times the original speed i.e. '4v'. Note that all the parameters remain to be same.
[19] What is the maximum value of deforming force up to which a material shows elastic property and above which the material loses it?
A.
Elasticity
B.
Strain
C.
Elastic Limit
D.
Stress
Ans:
Stress
Explanation :
The Maximum Extent to which a solid may be stretched without permanent alteration of size or shape.
[20] The method of protecting iron from rusting, by coating a thin layer of Zinc is called -
A.
Galvanizing
B.
rancidity
C.
Alloy
D.
Pulverizing
Ans:
Galvanizing
Explanation :
Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting.
[21] Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by –
A.
Carbon dioxide
B.
Ammonia
C.
Chlorine
D.
Ozone
Ans:
Ozone
Explanation :
The ozone layer absorbs 97-99% of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Ozone is formed from di- oxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
[22] "Curie" is unit of :
A.
Radioactivity
B.
Temperature
C.
Heat
D.
Energy
Ans:
Radioactivity
Explanation :
Curie, in physics, unit of activity of a quantity of a radioactive substance, named in honour of the French physicist Marie Curie. One curie (1 Ci) is equal to 3.7 x 1010 Becquerel (Bq). Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.
[23] Speed of sound is the greatest in :
A.
Water
B.
Air
C.
Glass
D.
Glycerine
Ans:
Glass
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
X-rays are part of the electromagnetic spectrum, an ionizing radiation with wavelengths shorter than ultraviolet light. X-ray tubes evolved from experimental Crookes tubes with which X-rays were first discovered in the late 19th century, and the availability of this controllable source of X-rays created the field of radiography, the imaging of opaque objects with penetrating radiation.
[16] Which of the following is used for regulated electric supply?
A.
Zener diode
B.
Junction diode
C.
Gun diode
D.
Tunnel diode
Ans:
Zener diode
Explanation :
The Zener diode is like a general-purpose signal diode. When based in the forward direction it behaves just like a normal signal diode, but when a reverse voltage is applied to it, the voltage remains constant for a wide range of currents and hence widely used for regulated electric supply. The device was named after Clarence Zener, who discovered this electrical property. Many diodes described as “Zener” diodes rely instead on avalanche breakdown as the mechanism. Common applications include providing a reference voltage for voltage regulators, or to protect other semiconductor devices from momentary voltage pulses. Zener diodes are widely used as voltage references and as shunt regulators to regulate the voltage across small circuits.
[17] What is found in frequency modulation?
A.
Fixed frequency
B.
Fixed dimension
C.
Change in frequency and dimension
D.
Change in dimension only
Ans:
Fixed frequency
Explanation :
Frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant. Frequency modulation is also used in telemetry, radar, seismic prospecting and newborn EEG seizure monitoring.
[18] When the speed of car is doubled, then what will be the braking force of the car to stop it in the same distance?
A.
four times
B.
two times
C.
half
D.
one-fourth
Ans:
four times
Explanation :
Brake force, also known as Brake Power, is a measure of braking power of a vehicle. Suppose a car whose mass is 'x' and is braked from a speed of y km/hr to come to halt at a uniform retardation in z min. If the speed of the car is doubled in the same distance, then the braking force required to stop the car is four times the original speed i.e. '4v'. Note that all the parameters remain to be same.
[19] What is the maximum value of deforming force up to which a material shows elastic property and above which the material loses it?
A.
Elasticity
B.
Strain
C.
Elastic Limit
D.
Stress
Ans:
Stress
Explanation :
The Maximum Extent to which a solid may be stretched without permanent alteration of size or shape.
[20] The method of protecting iron from rusting, by coating a thin layer of Zinc is called -
A.
Galvanizing
B.
rancidity
C.
Alloy
D.
Pulverizing
Ans:
Galvanizing
Explanation :
Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting.
[21] Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by –
A.
Carbon dioxide
B.
Ammonia
C.
Chlorine
D.
Ozone
Ans:
Ozone
Explanation :
The ozone layer absorbs 97-99% of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Ozone is formed from di- oxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
[22] "Curie" is unit of :
A.
Radioactivity
B.
Temperature
C.
Heat
D.
Energy
Ans:
Radioactivity
Explanation :
Curie, in physics, unit of activity of a quantity of a radioactive substance, named in honour of the French physicist Marie Curie. One curie (1 Ci) is equal to 3.7 x 1010 Becquerel (Bq). Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.
[23] Speed of sound is the greatest in :
A.
Water
B.
Air
C.
Glass
D.
Glycerine
Ans:
Glass
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
Frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant. Frequency modulation is also used in telemetry, radar, seismic prospecting and newborn EEG seizure monitoring.
[18] When the speed of car is doubled, then what will be the braking force of the car to stop it in the same distance?
A.
four times
B.
two times
C.
half
D.
one-fourth
Ans:
four times
Explanation :
Brake force, also known as Brake Power, is a measure of braking power of a vehicle. Suppose a car whose mass is 'x' and is braked from a speed of y km/hr to come to halt at a uniform retardation in z min. If the speed of the car is doubled in the same distance, then the braking force required to stop the car is four times the original speed i.e. '4v'. Note that all the parameters remain to be same.
[19] What is the maximum value of deforming force up to which a material shows elastic property and above which the material loses it?
A.
Elasticity
B.
Strain
C.
Elastic Limit
D.
Stress
Ans:
Stress
Explanation :
The Maximum Extent to which a solid may be stretched without permanent alteration of size or shape.
[20] The method of protecting iron from rusting, by coating a thin layer of Zinc is called -
A.
Galvanizing
B.
rancidity
C.
Alloy
D.
Pulverizing
Ans:
Galvanizing
Explanation :
Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting.
[21] Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by –
A.
Carbon dioxide
B.
Ammonia
C.
Chlorine
D.
Ozone
Ans:
Ozone
Explanation :
The ozone layer absorbs 97-99% of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Ozone is formed from di- oxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
[22] "Curie" is unit of :
A.
Radioactivity
B.
Temperature
C.
Heat
D.
Energy
Ans:
Radioactivity
Explanation :
Curie, in physics, unit of activity of a quantity of a radioactive substance, named in honour of the French physicist Marie Curie. One curie (1 Ci) is equal to 3.7 x 1010 Becquerel (Bq). Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.
[23] Speed of sound is the greatest in :
A.
Water
B.
Air
C.
Glass
D.
Glycerine
Ans:
Glass
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
The Maximum Extent to which a solid may be stretched without permanent alteration of size or shape.
[20] The method of protecting iron from rusting, by coating a thin layer of Zinc is called -
A.
Galvanizing
B.
rancidity
C.
Alloy
D.
Pulverizing
Ans:
Galvanizing
Explanation :
Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting.
[21] Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by –
A.
Carbon dioxide
B.
Ammonia
C.
Chlorine
D.
Ozone
Ans:
Ozone
Explanation :
The ozone layer absorbs 97-99% of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Ozone is formed from di- oxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
[22] "Curie" is unit of :
A.
Radioactivity
B.
Temperature
C.
Heat
D.
Energy
Ans:
Radioactivity
Explanation :
Curie, in physics, unit of activity of a quantity of a radioactive substance, named in honour of the French physicist Marie Curie. One curie (1 Ci) is equal to 3.7 x 1010 Becquerel (Bq). Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.
[23] Speed of sound is the greatest in :
A.
Water
B.
Air
C.
Glass
D.
Glycerine
Ans:
Glass
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
The ozone layer absorbs 97-99% of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Ozone is formed from di- oxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.
[22] "Curie" is unit of :
A.
Radioactivity
B.
Temperature
C.
Heat
D.
Energy
Ans:
Radioactivity
Explanation :
Curie, in physics, unit of activity of a quantity of a radioactive substance, named in honour of the French physicist Marie Curie. One curie (1 Ci) is equal to 3.7 x 1010 Becquerel (Bq). Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.
[23] Speed of sound is the greatest in :
A.
Water
B.
Air
C.
Glass
D.
Glycerine
Ans:
Glass
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
Sound travels faster in liquids and non-porous solids than it does in air. It travels about 4.3 times as fast in water (1,484 m/s), and nearly 15 times as fast in iron (5,120 m/s), than in air at 20 degrees Celsius.
[24] Laser is a device to produce -
A.
a beam of white light
B.
coherent light
C.
microwaves
D.
X-rays
Ans:
coherent light
Explanation :
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform. Coherence is an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference.
[25] The hydraulic brakes used in automobiles is a direct application of :
A.
Archimedes' principle
B.
Toricellian law
C.
Bernoulli's theorem
D.
Pascal's law
Ans:
Pascal's law
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.
Explanation :
Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.