[1] A gap is left between two rails of a railway track to accommodate of the metal.
A.
areal expansion
B.
volume expansion
C.
liner expansion
D.
apparent expansion
Ans:
liner expansion
Explanation :
The volume of materials changes depending on current temperature. Usually heat makes them expand, and cold leads them to contract. To a first approximation, the change in length measurements of an object ("linear dimension" as opposed to, e.g., volumetric dimension) due to thermal expansion is related to temperature change by a "linear expansion coefficient". It is the fractional change in length per degree of temperature change.
[2] If an ordinary glass tube and a glass capillary tube are 'both clipped in a beaker of water, water rises in –
A.
both
B.
only the glass tube
C.
only the capillary tube
D.
neither
Ans:
both
Explanation :
The rise or fall of liquid due to capillarity in a beaker of water depends upon the radius of the bore of the tube (s) which is/are dipped into it. The narrower the bore of the tube, the greater is the rise or fall of the liquid in the tube. So in this case, water will rise in both the glass tube and the glass capillary tube.
[3] Optical fibres are based on the phenomenon of –
A.
Interference
B.
Dispersion
C.
Diffraction
D.
Total Internal Reflection
Ans:
Total Internal Reflection
Explanation :
An optical fiber (or optical fibre) is a flexible, transparent fiber made of glass (Silica) or plastic, slightly thicker than a human hair. It functions as a waveguide, or "light pipe", to transmit light between the two ends of the fiber. Optical fibers typically include a transparent core surrounded by a transparent cladding material with a lower index of refraction. Light is kept in the core by total internal reflection. This causes the fiber to act as a waveguide.
[4] Who was the inventor of frozen foods?
A.
Alfred Nobel
B.
Clarence Birdseye
C.
Frank Whittle
D.
Ives McGaffey
Ans:
Clarence Birdseye
Explanation :
Clarence Birdseye, an American entrepreneur, and naturalist, is considered to be the founder of the modern frozen food industry. He invented the quick-freezing method in 1924, which produces the type of frozen foods that we know today.
[5] The clouds float in the atmosphere because of their low:
A.
temperature
B.
velocity
C.
pressure
D.
density
Ans:
density
Explanation :
Clouds generally form, survive and grow in air that is moving upward. Rising air expands as the pressure on it decreases, and that expansion into thinner, high-altitude air causes cooling.
[6] A person is hurt on kicking a stone due to –
A.
Inertia
B.
Velocity
C.
Reaction
D.
Momentum
Ans:
Reaction
Explanation :
Newton's third law states that "For every action, there is an equal and opposite reaction." The statement means that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object. So harder the stone is kicked, the harder will be its effect on the hitter.
[7] The fuse in our domestic electric circuit melts when there is a high rise in –
A.
Inductance
B.
Current
C.
Resistance
D.
Capacitance
Ans:
Current
Explanation :
In electronics and electrical engineering, a fuse is a type of low resistance resistor that acts as a sacrificial device to provide over protection, of either the load or source circuit. It's essential component is a metal wire or strip that melts when too much current flows, which interrupts the circuit in which it is connected. Short circuit, overloading, mismatched loads or device failure are the prime reasons for excessive current. A fuse interrupts excessive current (blows) so that further damage by overheating or fire is prevented.
[8] The energy stored in a watch spring is –
A.
Kinetic energy
B.
Potential energy
C.
Heat energy
D.
Chemical energy
Ans:
Potential energy
Explanation :
The energy stored in a spring of a watch is potential energy which is as a result of winding of the string. This energy is used to run the watch as it converts this potential energy to rotational kinetic energy. Windup watches function due to the winding of a small dial on the outside of the watch. This dial transfers the energy produced by your hand to the internal components of the watch.
[9] Cryogenics is a science deals with -
A.
High Temperatures
B.
Low Pressure
C.
High Pressure
D.
Low Temperature
Ans:
Low Temperature
Explanation :
Cryogenics is the study of how to get to low temperatures and of how materials behave when they get there. Besides the familiar temperature scales of Fahrenheit and Celsius (Centigrade), cryogenicists use other temperature scales, the Kelvin and Rankine temperature scales. One of the more modern processes being used to treat metals (as well as other materials) is cryogenic tempering. While the science of heat treatment is well known and widely understood, the principles of cryogenic tempering remain a mystery to most people in industry.
[10] `Short-sight' in human eye can be corrected by using proper –
A.
convex lens
B.
concave lens
C.
cylindrical lens
D.
bifocal lens
Ans:
concave lens
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth's atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation.
[11] What is the reason for twinkling of stars?
A.
Dispersion of light
B.
Total internal reflection
C.
Atmospheric reflection
D.
Atmospheric refraction
Ans:
Atmospheric refraction
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth’s atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation. As one of the three principal factors governing astronomical seeing, atmospheric scintillation is defined as variations in illuminance only. Scintillation does not cause images of planets to flicker. Most scintillation effects are caused by anomalous refraction caused by small-scale fluctuations in air density usually related to temperature gradients.
[12] Which gas is used in filling electric bulbs -
A.
Neon
B.
Argon
C.
Radon
D.
Krypton
Ans:
Argon
Explanation :
Argon is used to fill incandescent light bulbs to inhibit the evaporation of the tungsten filaments and increase bulb life.
[13] Ball pen functions on the principle of :
A.
Viscosity
B.
Boyle's Law
C.
Gravitational force
D.
Surface tension
Ans:
Surface tension
Explanation :
The ballpoint pen is one of the most simple and yet ubiquitous devices whose function depends on surface tension. With a pen held upright, gravity and surface tension act in concert to get ink onto the ball.
[14] A man cannot see clearly beyond 10 meters. The disease he suffers from :
A.
Far sight
B.
Myopia
C.
Cataract
D.
Hypermetropia
Ans:
Myopia
Explanation :
The man suffers from myopia, a vision condition in which close objects are seen clearly, but objects farther away appear blurred. Nearsightedness occurs if the eyeball is too long or the cornea, the clear front cover of the eye, has too much curvature. As a result, the light entering the eye isn't focused correctly and distant objects look blurred.
[15] The S.I. unit of electric charge is –
A.
ampere
B.
coulomb
C.
e.s.u
D.
Kelvin
Ans:
coulomb
Explanation :
The SI unit of quantity of electric charge is the coulomb, which is equivalent to about 6.242x1018 e (e is the charge of a proton). Hence, the charge of an electron is approximately -1.602x10-19 C. The coulomb is defined as the quantity of charge that has passed through the cross section of an electrical conductor carrying one ampere within one second.
[16] Light beam which is highly directional is called:
A.
eraser
B.
grazer
C.
maser
D.
laser
Ans:
laser
Explanation :
Laser light is very different from normal light. It is very directional, has a very tight beam and is very strong and concentrated. The light released is monochromatic. It contains one specific wavelength of light (one specific colour).
[17] Permissible noise level at Residential area during night time is :
A.
45 dB
B.
55 dB
C.
75 dB
D.
80 dB
Ans:
45 dB
Explanation :
As per the norm, the permissible noise level in residential areas is 45 db during night time, 55 db during day and in commercial areas it is 55 db during night and 65 db during day.
[18] When milk is churned, the cream separates from it clue to:
A.
Frictional force
B.
Centrifugal force
C.
Gravitation al force
D.
Viscous forces
Ans:
Centrifugal force
Explanation :
The extraction of cream happens because of the work of centrifugal force which works outward. The separation of cream from milk is based on the fact that when liquids of different specific gravities revolve around the same centre at the same distance with the same angular velocity, a greater centrifugal force is exerted on the heavier liquid than on the lighter one. Milk can be regarded as two liquids of different specific gravities, the serum and the fat.
[19] Moving electric charge produces -
A.
magnetic field
B.
sound waves
C.
light rays
D.
heat waves
Ans:
magnetic field
Explanation :
An electric charge always produces an electric field, regardless of speed, and a moving charge generates a magnetic field. An electric current passing through a conductor produces a magnetic field because it has many charges in motion.
[20] The process of union of two or more molecules of a substance to form a large single molecule is called :
A.
Fusion
B.
Diffusion
C.
Polymerization
D.
Synthesis
Ans:
Polymerization
Explanation :
Polymerisation is the chemical process of monomers joining together to form polymers, often it takes many thousands of monomers to make a single polymer.
[21] When a barometer reading suddenly recedes, it indicates that climate –
A.
will be very warm
B.
will be extremely stormy
C.
will remain cold
D.
incessant rain for at least 48 hours
Ans:
will be extremely stormy
Explanation :
In summer, when the barometer falls suddenly, a thunderstorm can be expected, and if it does not rise again upon its cessation, the weather will probably continue unsettled for several days. In summer, when a thunderstorm happens, there is little or no depression of the barometer.
[22] Which colour of light shows maximum deviation when passed through a prism?
A.
White
B.
Red
C.
Violet
D.
Green
Ans:
Violet
Explanation :
The angle of deviation, by which the light of a particular wavelength gets deviated on passing through a medium, depends upon the refractive index of the medium, as encountered by that light wavelength. The smaller the wavelength of the passing light, the greater is the refractive index observed.
[23] The best material for the core of a transformer is –
A.
stainless steel
B.
mild steel
C.
hard steel
D.
soft iron
Ans:
soft iron
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
The volume of materials changes depending on current temperature. Usually heat makes them expand, and cold leads them to contract. To a first approximation, the change in length measurements of an object ("linear dimension" as opposed to, e.g., volumetric dimension) due to thermal expansion is related to temperature change by a "linear expansion coefficient". It is the fractional change in length per degree of temperature change.
[2] If an ordinary glass tube and a glass capillary tube are 'both clipped in a beaker of water, water rises in –
A.
both
B.
only the glass tube
C.
only the capillary tube
D.
neither
Ans:
both
Explanation :
The rise or fall of liquid due to capillarity in a beaker of water depends upon the radius of the bore of the tube (s) which is/are dipped into it. The narrower the bore of the tube, the greater is the rise or fall of the liquid in the tube. So in this case, water will rise in both the glass tube and the glass capillary tube.
[3] Optical fibres are based on the phenomenon of –
A.
Interference
B.
Dispersion
C.
Diffraction
D.
Total Internal Reflection
Ans:
Total Internal Reflection
Explanation :
An optical fiber (or optical fibre) is a flexible, transparent fiber made of glass (Silica) or plastic, slightly thicker than a human hair. It functions as a waveguide, or "light pipe", to transmit light between the two ends of the fiber. Optical fibers typically include a transparent core surrounded by a transparent cladding material with a lower index of refraction. Light is kept in the core by total internal reflection. This causes the fiber to act as a waveguide.
[4] Who was the inventor of frozen foods?
A.
Alfred Nobel
B.
Clarence Birdseye
C.
Frank Whittle
D.
Ives McGaffey
Ans:
Clarence Birdseye
Explanation :
Clarence Birdseye, an American entrepreneur, and naturalist, is considered to be the founder of the modern frozen food industry. He invented the quick-freezing method in 1924, which produces the type of frozen foods that we know today.
[5] The clouds float in the atmosphere because of their low:
A.
temperature
B.
velocity
C.
pressure
D.
density
Ans:
density
Explanation :
Clouds generally form, survive and grow in air that is moving upward. Rising air expands as the pressure on it decreases, and that expansion into thinner, high-altitude air causes cooling.
[6] A person is hurt on kicking a stone due to –
A.
Inertia
B.
Velocity
C.
Reaction
D.
Momentum
Ans:
Reaction
Explanation :
Newton's third law states that "For every action, there is an equal and opposite reaction." The statement means that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object. So harder the stone is kicked, the harder will be its effect on the hitter.
[7] The fuse in our domestic electric circuit melts when there is a high rise in –
A.
Inductance
B.
Current
C.
Resistance
D.
Capacitance
Ans:
Current
Explanation :
In electronics and electrical engineering, a fuse is a type of low resistance resistor that acts as a sacrificial device to provide over protection, of either the load or source circuit. It's essential component is a metal wire or strip that melts when too much current flows, which interrupts the circuit in which it is connected. Short circuit, overloading, mismatched loads or device failure are the prime reasons for excessive current. A fuse interrupts excessive current (blows) so that further damage by overheating or fire is prevented.
[8] The energy stored in a watch spring is –
A.
Kinetic energy
B.
Potential energy
C.
Heat energy
D.
Chemical energy
Ans:
Potential energy
Explanation :
The energy stored in a spring of a watch is potential energy which is as a result of winding of the string. This energy is used to run the watch as it converts this potential energy to rotational kinetic energy. Windup watches function due to the winding of a small dial on the outside of the watch. This dial transfers the energy produced by your hand to the internal components of the watch.
[9] Cryogenics is a science deals with -
A.
High Temperatures
B.
Low Pressure
C.
High Pressure
D.
Low Temperature
Ans:
Low Temperature
Explanation :
Cryogenics is the study of how to get to low temperatures and of how materials behave when they get there. Besides the familiar temperature scales of Fahrenheit and Celsius (Centigrade), cryogenicists use other temperature scales, the Kelvin and Rankine temperature scales. One of the more modern processes being used to treat metals (as well as other materials) is cryogenic tempering. While the science of heat treatment is well known and widely understood, the principles of cryogenic tempering remain a mystery to most people in industry.
[10] `Short-sight' in human eye can be corrected by using proper –
A.
convex lens
B.
concave lens
C.
cylindrical lens
D.
bifocal lens
Ans:
concave lens
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth's atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation.
[11] What is the reason for twinkling of stars?
A.
Dispersion of light
B.
Total internal reflection
C.
Atmospheric reflection
D.
Atmospheric refraction
Ans:
Atmospheric refraction
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth’s atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation. As one of the three principal factors governing astronomical seeing, atmospheric scintillation is defined as variations in illuminance only. Scintillation does not cause images of planets to flicker. Most scintillation effects are caused by anomalous refraction caused by small-scale fluctuations in air density usually related to temperature gradients.
[12] Which gas is used in filling electric bulbs -
A.
Neon
B.
Argon
C.
Radon
D.
Krypton
Ans:
Argon
Explanation :
Argon is used to fill incandescent light bulbs to inhibit the evaporation of the tungsten filaments and increase bulb life.
[13] Ball pen functions on the principle of :
A.
Viscosity
B.
Boyle's Law
C.
Gravitational force
D.
Surface tension
Ans:
Surface tension
Explanation :
The ballpoint pen is one of the most simple and yet ubiquitous devices whose function depends on surface tension. With a pen held upright, gravity and surface tension act in concert to get ink onto the ball.
[14] A man cannot see clearly beyond 10 meters. The disease he suffers from :
A.
Far sight
B.
Myopia
C.
Cataract
D.
Hypermetropia
Ans:
Myopia
Explanation :
The man suffers from myopia, a vision condition in which close objects are seen clearly, but objects farther away appear blurred. Nearsightedness occurs if the eyeball is too long or the cornea, the clear front cover of the eye, has too much curvature. As a result, the light entering the eye isn't focused correctly and distant objects look blurred.
[15] The S.I. unit of electric charge is –
A.
ampere
B.
coulomb
C.
e.s.u
D.
Kelvin
Ans:
coulomb
Explanation :
The SI unit of quantity of electric charge is the coulomb, which is equivalent to about 6.242x1018 e (e is the charge of a proton). Hence, the charge of an electron is approximately -1.602x10-19 C. The coulomb is defined as the quantity of charge that has passed through the cross section of an electrical conductor carrying one ampere within one second.
[16] Light beam which is highly directional is called:
A.
eraser
B.
grazer
C.
maser
D.
laser
Ans:
laser
Explanation :
Laser light is very different from normal light. It is very directional, has a very tight beam and is very strong and concentrated. The light released is monochromatic. It contains one specific wavelength of light (one specific colour).
[17] Permissible noise level at Residential area during night time is :
A.
45 dB
B.
55 dB
C.
75 dB
D.
80 dB
Ans:
45 dB
Explanation :
As per the norm, the permissible noise level in residential areas is 45 db during night time, 55 db during day and in commercial areas it is 55 db during night and 65 db during day.
[18] When milk is churned, the cream separates from it clue to:
A.
Frictional force
B.
Centrifugal force
C.
Gravitation al force
D.
Viscous forces
Ans:
Centrifugal force
Explanation :
The extraction of cream happens because of the work of centrifugal force which works outward. The separation of cream from milk is based on the fact that when liquids of different specific gravities revolve around the same centre at the same distance with the same angular velocity, a greater centrifugal force is exerted on the heavier liquid than on the lighter one. Milk can be regarded as two liquids of different specific gravities, the serum and the fat.
[19] Moving electric charge produces -
A.
magnetic field
B.
sound waves
C.
light rays
D.
heat waves
Ans:
magnetic field
Explanation :
An electric charge always produces an electric field, regardless of speed, and a moving charge generates a magnetic field. An electric current passing through a conductor produces a magnetic field because it has many charges in motion.
[20] The process of union of two or more molecules of a substance to form a large single molecule is called :
A.
Fusion
B.
Diffusion
C.
Polymerization
D.
Synthesis
Ans:
Polymerization
Explanation :
Polymerisation is the chemical process of monomers joining together to form polymers, often it takes many thousands of monomers to make a single polymer.
[21] When a barometer reading suddenly recedes, it indicates that climate –
A.
will be very warm
B.
will be extremely stormy
C.
will remain cold
D.
incessant rain for at least 48 hours
Ans:
will be extremely stormy
Explanation :
In summer, when the barometer falls suddenly, a thunderstorm can be expected, and if it does not rise again upon its cessation, the weather will probably continue unsettled for several days. In summer, when a thunderstorm happens, there is little or no depression of the barometer.
[22] Which colour of light shows maximum deviation when passed through a prism?
A.
White
B.
Red
C.
Violet
D.
Green
Ans:
Violet
Explanation :
The angle of deviation, by which the light of a particular wavelength gets deviated on passing through a medium, depends upon the refractive index of the medium, as encountered by that light wavelength. The smaller the wavelength of the passing light, the greater is the refractive index observed.
[23] The best material for the core of a transformer is –
A.
stainless steel
B.
mild steel
C.
hard steel
D.
soft iron
Ans:
soft iron
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
An optical fiber (or optical fibre) is a flexible, transparent fiber made of glass (Silica) or plastic, slightly thicker than a human hair. It functions as a waveguide, or "light pipe", to transmit light between the two ends of the fiber. Optical fibers typically include a transparent core surrounded by a transparent cladding material with a lower index of refraction. Light is kept in the core by total internal reflection. This causes the fiber to act as a waveguide.
[4] Who was the inventor of frozen foods?
A.
Alfred Nobel
B.
Clarence Birdseye
C.
Frank Whittle
D.
Ives McGaffey
Ans:
Clarence Birdseye
Explanation :
Clarence Birdseye, an American entrepreneur, and naturalist, is considered to be the founder of the modern frozen food industry. He invented the quick-freezing method in 1924, which produces the type of frozen foods that we know today.
[5] The clouds float in the atmosphere because of their low:
A.
temperature
B.
velocity
C.
pressure
D.
density
Ans:
density
Explanation :
Clouds generally form, survive and grow in air that is moving upward. Rising air expands as the pressure on it decreases, and that expansion into thinner, high-altitude air causes cooling.
[6] A person is hurt on kicking a stone due to –
A.
Inertia
B.
Velocity
C.
Reaction
D.
Momentum
Ans:
Reaction
Explanation :
Newton's third law states that "For every action, there is an equal and opposite reaction." The statement means that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object. So harder the stone is kicked, the harder will be its effect on the hitter.
[7] The fuse in our domestic electric circuit melts when there is a high rise in –
A.
Inductance
B.
Current
C.
Resistance
D.
Capacitance
Ans:
Current
Explanation :
In electronics and electrical engineering, a fuse is a type of low resistance resistor that acts as a sacrificial device to provide over protection, of either the load or source circuit. It's essential component is a metal wire or strip that melts when too much current flows, which interrupts the circuit in which it is connected. Short circuit, overloading, mismatched loads or device failure are the prime reasons for excessive current. A fuse interrupts excessive current (blows) so that further damage by overheating or fire is prevented.
[8] The energy stored in a watch spring is –
A.
Kinetic energy
B.
Potential energy
C.
Heat energy
D.
Chemical energy
Ans:
Potential energy
Explanation :
The energy stored in a spring of a watch is potential energy which is as a result of winding of the string. This energy is used to run the watch as it converts this potential energy to rotational kinetic energy. Windup watches function due to the winding of a small dial on the outside of the watch. This dial transfers the energy produced by your hand to the internal components of the watch.
[9] Cryogenics is a science deals with -
A.
High Temperatures
B.
Low Pressure
C.
High Pressure
D.
Low Temperature
Ans:
Low Temperature
Explanation :
Cryogenics is the study of how to get to low temperatures and of how materials behave when they get there. Besides the familiar temperature scales of Fahrenheit and Celsius (Centigrade), cryogenicists use other temperature scales, the Kelvin and Rankine temperature scales. One of the more modern processes being used to treat metals (as well as other materials) is cryogenic tempering. While the science of heat treatment is well known and widely understood, the principles of cryogenic tempering remain a mystery to most people in industry.
[10] `Short-sight' in human eye can be corrected by using proper –
A.
convex lens
B.
concave lens
C.
cylindrical lens
D.
bifocal lens
Ans:
concave lens
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth's atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation.
[11] What is the reason for twinkling of stars?
A.
Dispersion of light
B.
Total internal reflection
C.
Atmospheric reflection
D.
Atmospheric refraction
Ans:
Atmospheric refraction
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth’s atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation. As one of the three principal factors governing astronomical seeing, atmospheric scintillation is defined as variations in illuminance only. Scintillation does not cause images of planets to flicker. Most scintillation effects are caused by anomalous refraction caused by small-scale fluctuations in air density usually related to temperature gradients.
[12] Which gas is used in filling electric bulbs -
A.
Neon
B.
Argon
C.
Radon
D.
Krypton
Ans:
Argon
Explanation :
Argon is used to fill incandescent light bulbs to inhibit the evaporation of the tungsten filaments and increase bulb life.
[13] Ball pen functions on the principle of :
A.
Viscosity
B.
Boyle's Law
C.
Gravitational force
D.
Surface tension
Ans:
Surface tension
Explanation :
The ballpoint pen is one of the most simple and yet ubiquitous devices whose function depends on surface tension. With a pen held upright, gravity and surface tension act in concert to get ink onto the ball.
[14] A man cannot see clearly beyond 10 meters. The disease he suffers from :
A.
Far sight
B.
Myopia
C.
Cataract
D.
Hypermetropia
Ans:
Myopia
Explanation :
The man suffers from myopia, a vision condition in which close objects are seen clearly, but objects farther away appear blurred. Nearsightedness occurs if the eyeball is too long or the cornea, the clear front cover of the eye, has too much curvature. As a result, the light entering the eye isn't focused correctly and distant objects look blurred.
[15] The S.I. unit of electric charge is –
A.
ampere
B.
coulomb
C.
e.s.u
D.
Kelvin
Ans:
coulomb
Explanation :
The SI unit of quantity of electric charge is the coulomb, which is equivalent to about 6.242x1018 e (e is the charge of a proton). Hence, the charge of an electron is approximately -1.602x10-19 C. The coulomb is defined as the quantity of charge that has passed through the cross section of an electrical conductor carrying one ampere within one second.
[16] Light beam which is highly directional is called:
A.
eraser
B.
grazer
C.
maser
D.
laser
Ans:
laser
Explanation :
Laser light is very different from normal light. It is very directional, has a very tight beam and is very strong and concentrated. The light released is monochromatic. It contains one specific wavelength of light (one specific colour).
[17] Permissible noise level at Residential area during night time is :
A.
45 dB
B.
55 dB
C.
75 dB
D.
80 dB
Ans:
45 dB
Explanation :
As per the norm, the permissible noise level in residential areas is 45 db during night time, 55 db during day and in commercial areas it is 55 db during night and 65 db during day.
[18] When milk is churned, the cream separates from it clue to:
A.
Frictional force
B.
Centrifugal force
C.
Gravitation al force
D.
Viscous forces
Ans:
Centrifugal force
Explanation :
The extraction of cream happens because of the work of centrifugal force which works outward. The separation of cream from milk is based on the fact that when liquids of different specific gravities revolve around the same centre at the same distance with the same angular velocity, a greater centrifugal force is exerted on the heavier liquid than on the lighter one. Milk can be regarded as two liquids of different specific gravities, the serum and the fat.
[19] Moving electric charge produces -
A.
magnetic field
B.
sound waves
C.
light rays
D.
heat waves
Ans:
magnetic field
Explanation :
An electric charge always produces an electric field, regardless of speed, and a moving charge generates a magnetic field. An electric current passing through a conductor produces a magnetic field because it has many charges in motion.
[20] The process of union of two or more molecules of a substance to form a large single molecule is called :
A.
Fusion
B.
Diffusion
C.
Polymerization
D.
Synthesis
Ans:
Polymerization
Explanation :
Polymerisation is the chemical process of monomers joining together to form polymers, often it takes many thousands of monomers to make a single polymer.
[21] When a barometer reading suddenly recedes, it indicates that climate –
A.
will be very warm
B.
will be extremely stormy
C.
will remain cold
D.
incessant rain for at least 48 hours
Ans:
will be extremely stormy
Explanation :
In summer, when the barometer falls suddenly, a thunderstorm can be expected, and if it does not rise again upon its cessation, the weather will probably continue unsettled for several days. In summer, when a thunderstorm happens, there is little or no depression of the barometer.
[22] Which colour of light shows maximum deviation when passed through a prism?
A.
White
B.
Red
C.
Violet
D.
Green
Ans:
Violet
Explanation :
The angle of deviation, by which the light of a particular wavelength gets deviated on passing through a medium, depends upon the refractive index of the medium, as encountered by that light wavelength. The smaller the wavelength of the passing light, the greater is the refractive index observed.
[23] The best material for the core of a transformer is –
A.
stainless steel
B.
mild steel
C.
hard steel
D.
soft iron
Ans:
soft iron
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
Clouds generally form, survive and grow in air that is moving upward. Rising air expands as the pressure on it decreases, and that expansion into thinner, high-altitude air causes cooling.
[6] A person is hurt on kicking a stone due to –
A.
Inertia
B.
Velocity
C.
Reaction
D.
Momentum
Ans:
Reaction
Explanation :
Newton's third law states that "For every action, there is an equal and opposite reaction." The statement means that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object. So harder the stone is kicked, the harder will be its effect on the hitter.
[7] The fuse in our domestic electric circuit melts when there is a high rise in –
A.
Inductance
B.
Current
C.
Resistance
D.
Capacitance
Ans:
Current
Explanation :
In electronics and electrical engineering, a fuse is a type of low resistance resistor that acts as a sacrificial device to provide over protection, of either the load or source circuit. It's essential component is a metal wire or strip that melts when too much current flows, which interrupts the circuit in which it is connected. Short circuit, overloading, mismatched loads or device failure are the prime reasons for excessive current. A fuse interrupts excessive current (blows) so that further damage by overheating or fire is prevented.
[8] The energy stored in a watch spring is –
A.
Kinetic energy
B.
Potential energy
C.
Heat energy
D.
Chemical energy
Ans:
Potential energy
Explanation :
The energy stored in a spring of a watch is potential energy which is as a result of winding of the string. This energy is used to run the watch as it converts this potential energy to rotational kinetic energy. Windup watches function due to the winding of a small dial on the outside of the watch. This dial transfers the energy produced by your hand to the internal components of the watch.
[9] Cryogenics is a science deals with -
A.
High Temperatures
B.
Low Pressure
C.
High Pressure
D.
Low Temperature
Ans:
Low Temperature
Explanation :
Cryogenics is the study of how to get to low temperatures and of how materials behave when they get there. Besides the familiar temperature scales of Fahrenheit and Celsius (Centigrade), cryogenicists use other temperature scales, the Kelvin and Rankine temperature scales. One of the more modern processes being used to treat metals (as well as other materials) is cryogenic tempering. While the science of heat treatment is well known and widely understood, the principles of cryogenic tempering remain a mystery to most people in industry.
[10] `Short-sight' in human eye can be corrected by using proper –
A.
convex lens
B.
concave lens
C.
cylindrical lens
D.
bifocal lens
Ans:
concave lens
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth's atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation.
[11] What is the reason for twinkling of stars?
A.
Dispersion of light
B.
Total internal reflection
C.
Atmospheric reflection
D.
Atmospheric refraction
Ans:
Atmospheric refraction
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth’s atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation. As one of the three principal factors governing astronomical seeing, atmospheric scintillation is defined as variations in illuminance only. Scintillation does not cause images of planets to flicker. Most scintillation effects are caused by anomalous refraction caused by small-scale fluctuations in air density usually related to temperature gradients.
[12] Which gas is used in filling electric bulbs -
A.
Neon
B.
Argon
C.
Radon
D.
Krypton
Ans:
Argon
Explanation :
Argon is used to fill incandescent light bulbs to inhibit the evaporation of the tungsten filaments and increase bulb life.
[13] Ball pen functions on the principle of :
A.
Viscosity
B.
Boyle's Law
C.
Gravitational force
D.
Surface tension
Ans:
Surface tension
Explanation :
The ballpoint pen is one of the most simple and yet ubiquitous devices whose function depends on surface tension. With a pen held upright, gravity and surface tension act in concert to get ink onto the ball.
[14] A man cannot see clearly beyond 10 meters. The disease he suffers from :
A.
Far sight
B.
Myopia
C.
Cataract
D.
Hypermetropia
Ans:
Myopia
Explanation :
The man suffers from myopia, a vision condition in which close objects are seen clearly, but objects farther away appear blurred. Nearsightedness occurs if the eyeball is too long or the cornea, the clear front cover of the eye, has too much curvature. As a result, the light entering the eye isn't focused correctly and distant objects look blurred.
[15] The S.I. unit of electric charge is –
A.
ampere
B.
coulomb
C.
e.s.u
D.
Kelvin
Ans:
coulomb
Explanation :
The SI unit of quantity of electric charge is the coulomb, which is equivalent to about 6.242x1018 e (e is the charge of a proton). Hence, the charge of an electron is approximately -1.602x10-19 C. The coulomb is defined as the quantity of charge that has passed through the cross section of an electrical conductor carrying one ampere within one second.
[16] Light beam which is highly directional is called:
A.
eraser
B.
grazer
C.
maser
D.
laser
Ans:
laser
Explanation :
Laser light is very different from normal light. It is very directional, has a very tight beam and is very strong and concentrated. The light released is monochromatic. It contains one specific wavelength of light (one specific colour).
[17] Permissible noise level at Residential area during night time is :
A.
45 dB
B.
55 dB
C.
75 dB
D.
80 dB
Ans:
45 dB
Explanation :
As per the norm, the permissible noise level in residential areas is 45 db during night time, 55 db during day and in commercial areas it is 55 db during night and 65 db during day.
[18] When milk is churned, the cream separates from it clue to:
A.
Frictional force
B.
Centrifugal force
C.
Gravitation al force
D.
Viscous forces
Ans:
Centrifugal force
Explanation :
The extraction of cream happens because of the work of centrifugal force which works outward. The separation of cream from milk is based on the fact that when liquids of different specific gravities revolve around the same centre at the same distance with the same angular velocity, a greater centrifugal force is exerted on the heavier liquid than on the lighter one. Milk can be regarded as two liquids of different specific gravities, the serum and the fat.
[19] Moving electric charge produces -
A.
magnetic field
B.
sound waves
C.
light rays
D.
heat waves
Ans:
magnetic field
Explanation :
An electric charge always produces an electric field, regardless of speed, and a moving charge generates a magnetic field. An electric current passing through a conductor produces a magnetic field because it has many charges in motion.
[20] The process of union of two or more molecules of a substance to form a large single molecule is called :
A.
Fusion
B.
Diffusion
C.
Polymerization
D.
Synthesis
Ans:
Polymerization
Explanation :
Polymerisation is the chemical process of monomers joining together to form polymers, often it takes many thousands of monomers to make a single polymer.
[21] When a barometer reading suddenly recedes, it indicates that climate –
A.
will be very warm
B.
will be extremely stormy
C.
will remain cold
D.
incessant rain for at least 48 hours
Ans:
will be extremely stormy
Explanation :
In summer, when the barometer falls suddenly, a thunderstorm can be expected, and if it does not rise again upon its cessation, the weather will probably continue unsettled for several days. In summer, when a thunderstorm happens, there is little or no depression of the barometer.
[22] Which colour of light shows maximum deviation when passed through a prism?
A.
White
B.
Red
C.
Violet
D.
Green
Ans:
Violet
Explanation :
The angle of deviation, by which the light of a particular wavelength gets deviated on passing through a medium, depends upon the refractive index of the medium, as encountered by that light wavelength. The smaller the wavelength of the passing light, the greater is the refractive index observed.
[23] The best material for the core of a transformer is –
A.
stainless steel
B.
mild steel
C.
hard steel
D.
soft iron
Ans:
soft iron
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
In electronics and electrical engineering, a fuse is a type of low resistance resistor that acts as a sacrificial device to provide over protection, of either the load or source circuit. It's essential component is a metal wire or strip that melts when too much current flows, which interrupts the circuit in which it is connected. Short circuit, overloading, mismatched loads or device failure are the prime reasons for excessive current. A fuse interrupts excessive current (blows) so that further damage by overheating or fire is prevented.
[8] The energy stored in a watch spring is –
A.
Kinetic energy
B.
Potential energy
C.
Heat energy
D.
Chemical energy
Ans:
Potential energy
Explanation :
The energy stored in a spring of a watch is potential energy which is as a result of winding of the string. This energy is used to run the watch as it converts this potential energy to rotational kinetic energy. Windup watches function due to the winding of a small dial on the outside of the watch. This dial transfers the energy produced by your hand to the internal components of the watch.
[9] Cryogenics is a science deals with -
A.
High Temperatures
B.
Low Pressure
C.
High Pressure
D.
Low Temperature
Ans:
Low Temperature
Explanation :
Cryogenics is the study of how to get to low temperatures and of how materials behave when they get there. Besides the familiar temperature scales of Fahrenheit and Celsius (Centigrade), cryogenicists use other temperature scales, the Kelvin and Rankine temperature scales. One of the more modern processes being used to treat metals (as well as other materials) is cryogenic tempering. While the science of heat treatment is well known and widely understood, the principles of cryogenic tempering remain a mystery to most people in industry.
[10] `Short-sight' in human eye can be corrected by using proper –
A.
convex lens
B.
concave lens
C.
cylindrical lens
D.
bifocal lens
Ans:
concave lens
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth's atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation.
[11] What is the reason for twinkling of stars?
A.
Dispersion of light
B.
Total internal reflection
C.
Atmospheric reflection
D.
Atmospheric refraction
Ans:
Atmospheric refraction
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth’s atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation. As one of the three principal factors governing astronomical seeing, atmospheric scintillation is defined as variations in illuminance only. Scintillation does not cause images of planets to flicker. Most scintillation effects are caused by anomalous refraction caused by small-scale fluctuations in air density usually related to temperature gradients.
[12] Which gas is used in filling electric bulbs -
A.
Neon
B.
Argon
C.
Radon
D.
Krypton
Ans:
Argon
Explanation :
Argon is used to fill incandescent light bulbs to inhibit the evaporation of the tungsten filaments and increase bulb life.
[13] Ball pen functions on the principle of :
A.
Viscosity
B.
Boyle's Law
C.
Gravitational force
D.
Surface tension
Ans:
Surface tension
Explanation :
The ballpoint pen is one of the most simple and yet ubiquitous devices whose function depends on surface tension. With a pen held upright, gravity and surface tension act in concert to get ink onto the ball.
[14] A man cannot see clearly beyond 10 meters. The disease he suffers from :
A.
Far sight
B.
Myopia
C.
Cataract
D.
Hypermetropia
Ans:
Myopia
Explanation :
The man suffers from myopia, a vision condition in which close objects are seen clearly, but objects farther away appear blurred. Nearsightedness occurs if the eyeball is too long or the cornea, the clear front cover of the eye, has too much curvature. As a result, the light entering the eye isn't focused correctly and distant objects look blurred.
[15] The S.I. unit of electric charge is –
A.
ampere
B.
coulomb
C.
e.s.u
D.
Kelvin
Ans:
coulomb
Explanation :
The SI unit of quantity of electric charge is the coulomb, which is equivalent to about 6.242x1018 e (e is the charge of a proton). Hence, the charge of an electron is approximately -1.602x10-19 C. The coulomb is defined as the quantity of charge that has passed through the cross section of an electrical conductor carrying one ampere within one second.
[16] Light beam which is highly directional is called:
A.
eraser
B.
grazer
C.
maser
D.
laser
Ans:
laser
Explanation :
Laser light is very different from normal light. It is very directional, has a very tight beam and is very strong and concentrated. The light released is monochromatic. It contains one specific wavelength of light (one specific colour).
[17] Permissible noise level at Residential area during night time is :
A.
45 dB
B.
55 dB
C.
75 dB
D.
80 dB
Ans:
45 dB
Explanation :
As per the norm, the permissible noise level in residential areas is 45 db during night time, 55 db during day and in commercial areas it is 55 db during night and 65 db during day.
[18] When milk is churned, the cream separates from it clue to:
A.
Frictional force
B.
Centrifugal force
C.
Gravitation al force
D.
Viscous forces
Ans:
Centrifugal force
Explanation :
The extraction of cream happens because of the work of centrifugal force which works outward. The separation of cream from milk is based on the fact that when liquids of different specific gravities revolve around the same centre at the same distance with the same angular velocity, a greater centrifugal force is exerted on the heavier liquid than on the lighter one. Milk can be regarded as two liquids of different specific gravities, the serum and the fat.
[19] Moving electric charge produces -
A.
magnetic field
B.
sound waves
C.
light rays
D.
heat waves
Ans:
magnetic field
Explanation :
An electric charge always produces an electric field, regardless of speed, and a moving charge generates a magnetic field. An electric current passing through a conductor produces a magnetic field because it has many charges in motion.
[20] The process of union of two or more molecules of a substance to form a large single molecule is called :
A.
Fusion
B.
Diffusion
C.
Polymerization
D.
Synthesis
Ans:
Polymerization
Explanation :
Polymerisation is the chemical process of monomers joining together to form polymers, often it takes many thousands of monomers to make a single polymer.
[21] When a barometer reading suddenly recedes, it indicates that climate –
A.
will be very warm
B.
will be extremely stormy
C.
will remain cold
D.
incessant rain for at least 48 hours
Ans:
will be extremely stormy
Explanation :
In summer, when the barometer falls suddenly, a thunderstorm can be expected, and if it does not rise again upon its cessation, the weather will probably continue unsettled for several days. In summer, when a thunderstorm happens, there is little or no depression of the barometer.
[22] Which colour of light shows maximum deviation when passed through a prism?
A.
White
B.
Red
C.
Violet
D.
Green
Ans:
Violet
Explanation :
The angle of deviation, by which the light of a particular wavelength gets deviated on passing through a medium, depends upon the refractive index of the medium, as encountered by that light wavelength. The smaller the wavelength of the passing light, the greater is the refractive index observed.
[23] The best material for the core of a transformer is –
A.
stainless steel
B.
mild steel
C.
hard steel
D.
soft iron
Ans:
soft iron
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
Cryogenics is the study of how to get to low temperatures and of how materials behave when they get there. Besides the familiar temperature scales of Fahrenheit and Celsius (Centigrade), cryogenicists use other temperature scales, the Kelvin and Rankine temperature scales. One of the more modern processes being used to treat metals (as well as other materials) is cryogenic tempering. While the science of heat treatment is well known and widely understood, the principles of cryogenic tempering remain a mystery to most people in industry.
[10] `Short-sight' in human eye can be corrected by using proper –
A.
convex lens
B.
concave lens
C.
cylindrical lens
D.
bifocal lens
Ans:
concave lens
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth's atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation.
[11] What is the reason for twinkling of stars?
A.
Dispersion of light
B.
Total internal reflection
C.
Atmospheric reflection
D.
Atmospheric refraction
Ans:
Atmospheric refraction
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth’s atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation. As one of the three principal factors governing astronomical seeing, atmospheric scintillation is defined as variations in illuminance only. Scintillation does not cause images of planets to flicker. Most scintillation effects are caused by anomalous refraction caused by small-scale fluctuations in air density usually related to temperature gradients.
[12] Which gas is used in filling electric bulbs -
A.
Neon
B.
Argon
C.
Radon
D.
Krypton
Ans:
Argon
Explanation :
Argon is used to fill incandescent light bulbs to inhibit the evaporation of the tungsten filaments and increase bulb life.
[13] Ball pen functions on the principle of :
A.
Viscosity
B.
Boyle's Law
C.
Gravitational force
D.
Surface tension
Ans:
Surface tension
Explanation :
The ballpoint pen is one of the most simple and yet ubiquitous devices whose function depends on surface tension. With a pen held upright, gravity and surface tension act in concert to get ink onto the ball.
[14] A man cannot see clearly beyond 10 meters. The disease he suffers from :
A.
Far sight
B.
Myopia
C.
Cataract
D.
Hypermetropia
Ans:
Myopia
Explanation :
The man suffers from myopia, a vision condition in which close objects are seen clearly, but objects farther away appear blurred. Nearsightedness occurs if the eyeball is too long or the cornea, the clear front cover of the eye, has too much curvature. As a result, the light entering the eye isn't focused correctly and distant objects look blurred.
[15] The S.I. unit of electric charge is –
A.
ampere
B.
coulomb
C.
e.s.u
D.
Kelvin
Ans:
coulomb
Explanation :
The SI unit of quantity of electric charge is the coulomb, which is equivalent to about 6.242x1018 e (e is the charge of a proton). Hence, the charge of an electron is approximately -1.602x10-19 C. The coulomb is defined as the quantity of charge that has passed through the cross section of an electrical conductor carrying one ampere within one second.
[16] Light beam which is highly directional is called:
A.
eraser
B.
grazer
C.
maser
D.
laser
Ans:
laser
Explanation :
Laser light is very different from normal light. It is very directional, has a very tight beam and is very strong and concentrated. The light released is monochromatic. It contains one specific wavelength of light (one specific colour).
[17] Permissible noise level at Residential area during night time is :
A.
45 dB
B.
55 dB
C.
75 dB
D.
80 dB
Ans:
45 dB
Explanation :
As per the norm, the permissible noise level in residential areas is 45 db during night time, 55 db during day and in commercial areas it is 55 db during night and 65 db during day.
[18] When milk is churned, the cream separates from it clue to:
A.
Frictional force
B.
Centrifugal force
C.
Gravitation al force
D.
Viscous forces
Ans:
Centrifugal force
Explanation :
The extraction of cream happens because of the work of centrifugal force which works outward. The separation of cream from milk is based on the fact that when liquids of different specific gravities revolve around the same centre at the same distance with the same angular velocity, a greater centrifugal force is exerted on the heavier liquid than on the lighter one. Milk can be regarded as two liquids of different specific gravities, the serum and the fat.
[19] Moving electric charge produces -
A.
magnetic field
B.
sound waves
C.
light rays
D.
heat waves
Ans:
magnetic field
Explanation :
An electric charge always produces an electric field, regardless of speed, and a moving charge generates a magnetic field. An electric current passing through a conductor produces a magnetic field because it has many charges in motion.
[20] The process of union of two or more molecules of a substance to form a large single molecule is called :
A.
Fusion
B.
Diffusion
C.
Polymerization
D.
Synthesis
Ans:
Polymerization
Explanation :
Polymerisation is the chemical process of monomers joining together to form polymers, often it takes many thousands of monomers to make a single polymer.
[21] When a barometer reading suddenly recedes, it indicates that climate –
A.
will be very warm
B.
will be extremely stormy
C.
will remain cold
D.
incessant rain for at least 48 hours
Ans:
will be extremely stormy
Explanation :
In summer, when the barometer falls suddenly, a thunderstorm can be expected, and if it does not rise again upon its cessation, the weather will probably continue unsettled for several days. In summer, when a thunderstorm happens, there is little or no depression of the barometer.
[22] Which colour of light shows maximum deviation when passed through a prism?
A.
White
B.
Red
C.
Violet
D.
Green
Ans:
Violet
Explanation :
The angle of deviation, by which the light of a particular wavelength gets deviated on passing through a medium, depends upon the refractive index of the medium, as encountered by that light wavelength. The smaller the wavelength of the passing light, the greater is the refractive index observed.
[23] The best material for the core of a transformer is –
A.
stainless steel
B.
mild steel
C.
hard steel
D.
soft iron
Ans:
soft iron
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If the object lies outside the Earth’s atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation. As one of the three principal factors governing astronomical seeing, atmospheric scintillation is defined as variations in illuminance only. Scintillation does not cause images of planets to flicker. Most scintillation effects are caused by anomalous refraction caused by small-scale fluctuations in air density usually related to temperature gradients.
[12] Which gas is used in filling electric bulbs -
A.
Neon
B.
Argon
C.
Radon
D.
Krypton
Ans:
Argon
Explanation :
Argon is used to fill incandescent light bulbs to inhibit the evaporation of the tungsten filaments and increase bulb life.
[13] Ball pen functions on the principle of :
A.
Viscosity
B.
Boyle's Law
C.
Gravitational force
D.
Surface tension
Ans:
Surface tension
Explanation :
The ballpoint pen is one of the most simple and yet ubiquitous devices whose function depends on surface tension. With a pen held upright, gravity and surface tension act in concert to get ink onto the ball.
[14] A man cannot see clearly beyond 10 meters. The disease he suffers from :
A.
Far sight
B.
Myopia
C.
Cataract
D.
Hypermetropia
Ans:
Myopia
Explanation :
The man suffers from myopia, a vision condition in which close objects are seen clearly, but objects farther away appear blurred. Nearsightedness occurs if the eyeball is too long or the cornea, the clear front cover of the eye, has too much curvature. As a result, the light entering the eye isn't focused correctly and distant objects look blurred.
[15] The S.I. unit of electric charge is –
A.
ampere
B.
coulomb
C.
e.s.u
D.
Kelvin
Ans:
coulomb
Explanation :
The SI unit of quantity of electric charge is the coulomb, which is equivalent to about 6.242x1018 e (e is the charge of a proton). Hence, the charge of an electron is approximately -1.602x10-19 C. The coulomb is defined as the quantity of charge that has passed through the cross section of an electrical conductor carrying one ampere within one second.
[16] Light beam which is highly directional is called:
A.
eraser
B.
grazer
C.
maser
D.
laser
Ans:
laser
Explanation :
Laser light is very different from normal light. It is very directional, has a very tight beam and is very strong and concentrated. The light released is monochromatic. It contains one specific wavelength of light (one specific colour).
[17] Permissible noise level at Residential area during night time is :
A.
45 dB
B.
55 dB
C.
75 dB
D.
80 dB
Ans:
45 dB
Explanation :
As per the norm, the permissible noise level in residential areas is 45 db during night time, 55 db during day and in commercial areas it is 55 db during night and 65 db during day.
[18] When milk is churned, the cream separates from it clue to:
A.
Frictional force
B.
Centrifugal force
C.
Gravitation al force
D.
Viscous forces
Ans:
Centrifugal force
Explanation :
The extraction of cream happens because of the work of centrifugal force which works outward. The separation of cream from milk is based on the fact that when liquids of different specific gravities revolve around the same centre at the same distance with the same angular velocity, a greater centrifugal force is exerted on the heavier liquid than on the lighter one. Milk can be regarded as two liquids of different specific gravities, the serum and the fat.
[19] Moving electric charge produces -
A.
magnetic field
B.
sound waves
C.
light rays
D.
heat waves
Ans:
magnetic field
Explanation :
An electric charge always produces an electric field, regardless of speed, and a moving charge generates a magnetic field. An electric current passing through a conductor produces a magnetic field because it has many charges in motion.
[20] The process of union of two or more molecules of a substance to form a large single molecule is called :
A.
Fusion
B.
Diffusion
C.
Polymerization
D.
Synthesis
Ans:
Polymerization
Explanation :
Polymerisation is the chemical process of monomers joining together to form polymers, often it takes many thousands of monomers to make a single polymer.
[21] When a barometer reading suddenly recedes, it indicates that climate –
A.
will be very warm
B.
will be extremely stormy
C.
will remain cold
D.
incessant rain for at least 48 hours
Ans:
will be extremely stormy
Explanation :
In summer, when the barometer falls suddenly, a thunderstorm can be expected, and if it does not rise again upon its cessation, the weather will probably continue unsettled for several days. In summer, when a thunderstorm happens, there is little or no depression of the barometer.
[22] Which colour of light shows maximum deviation when passed through a prism?
A.
White
B.
Red
C.
Violet
D.
Green
Ans:
Violet
Explanation :
The angle of deviation, by which the light of a particular wavelength gets deviated on passing through a medium, depends upon the refractive index of the medium, as encountered by that light wavelength. The smaller the wavelength of the passing light, the greater is the refractive index observed.
[23] The best material for the core of a transformer is –
A.
stainless steel
B.
mild steel
C.
hard steel
D.
soft iron
Ans:
soft iron
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
The ballpoint pen is one of the most simple and yet ubiquitous devices whose function depends on surface tension. With a pen held upright, gravity and surface tension act in concert to get ink onto the ball.
[14] A man cannot see clearly beyond 10 meters. The disease he suffers from :
A.
Far sight
B.
Myopia
C.
Cataract
D.
Hypermetropia
Ans:
Myopia
Explanation :
The man suffers from myopia, a vision condition in which close objects are seen clearly, but objects farther away appear blurred. Nearsightedness occurs if the eyeball is too long or the cornea, the clear front cover of the eye, has too much curvature. As a result, the light entering the eye isn't focused correctly and distant objects look blurred.
[15] The S.I. unit of electric charge is –
A.
ampere
B.
coulomb
C.
e.s.u
D.
Kelvin
Ans:
coulomb
Explanation :
The SI unit of quantity of electric charge is the coulomb, which is equivalent to about 6.242x1018 e (e is the charge of a proton). Hence, the charge of an electron is approximately -1.602x10-19 C. The coulomb is defined as the quantity of charge that has passed through the cross section of an electrical conductor carrying one ampere within one second.
[16] Light beam which is highly directional is called:
A.
eraser
B.
grazer
C.
maser
D.
laser
Ans:
laser
Explanation :
Laser light is very different from normal light. It is very directional, has a very tight beam and is very strong and concentrated. The light released is monochromatic. It contains one specific wavelength of light (one specific colour).
[17] Permissible noise level at Residential area during night time is :
A.
45 dB
B.
55 dB
C.
75 dB
D.
80 dB
Ans:
45 dB
Explanation :
As per the norm, the permissible noise level in residential areas is 45 db during night time, 55 db during day and in commercial areas it is 55 db during night and 65 db during day.
[18] When milk is churned, the cream separates from it clue to:
A.
Frictional force
B.
Centrifugal force
C.
Gravitation al force
D.
Viscous forces
Ans:
Centrifugal force
Explanation :
The extraction of cream happens because of the work of centrifugal force which works outward. The separation of cream from milk is based on the fact that when liquids of different specific gravities revolve around the same centre at the same distance with the same angular velocity, a greater centrifugal force is exerted on the heavier liquid than on the lighter one. Milk can be regarded as two liquids of different specific gravities, the serum and the fat.
[19] Moving electric charge produces -
A.
magnetic field
B.
sound waves
C.
light rays
D.
heat waves
Ans:
magnetic field
Explanation :
An electric charge always produces an electric field, regardless of speed, and a moving charge generates a magnetic field. An electric current passing through a conductor produces a magnetic field because it has many charges in motion.
[20] The process of union of two or more molecules of a substance to form a large single molecule is called :
A.
Fusion
B.
Diffusion
C.
Polymerization
D.
Synthesis
Ans:
Polymerization
Explanation :
Polymerisation is the chemical process of monomers joining together to form polymers, often it takes many thousands of monomers to make a single polymer.
[21] When a barometer reading suddenly recedes, it indicates that climate –
A.
will be very warm
B.
will be extremely stormy
C.
will remain cold
D.
incessant rain for at least 48 hours
Ans:
will be extremely stormy
Explanation :
In summer, when the barometer falls suddenly, a thunderstorm can be expected, and if it does not rise again upon its cessation, the weather will probably continue unsettled for several days. In summer, when a thunderstorm happens, there is little or no depression of the barometer.
[22] Which colour of light shows maximum deviation when passed through a prism?
A.
White
B.
Red
C.
Violet
D.
Green
Ans:
Violet
Explanation :
The angle of deviation, by which the light of a particular wavelength gets deviated on passing through a medium, depends upon the refractive index of the medium, as encountered by that light wavelength. The smaller the wavelength of the passing light, the greater is the refractive index observed.
[23] The best material for the core of a transformer is –
A.
stainless steel
B.
mild steel
C.
hard steel
D.
soft iron
Ans:
soft iron
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
The SI unit of quantity of electric charge is the coulomb, which is equivalent to about 6.242x1018 e (e is the charge of a proton). Hence, the charge of an electron is approximately -1.602x10-19 C. The coulomb is defined as the quantity of charge that has passed through the cross section of an electrical conductor carrying one ampere within one second.
[16] Light beam which is highly directional is called:
A.
eraser
B.
grazer
C.
maser
D.
laser
Ans:
laser
Explanation :
Laser light is very different from normal light. It is very directional, has a very tight beam and is very strong and concentrated. The light released is monochromatic. It contains one specific wavelength of light (one specific colour).
[17] Permissible noise level at Residential area during night time is :
A.
45 dB
B.
55 dB
C.
75 dB
D.
80 dB
Ans:
45 dB
Explanation :
As per the norm, the permissible noise level in residential areas is 45 db during night time, 55 db during day and in commercial areas it is 55 db during night and 65 db during day.
[18] When milk is churned, the cream separates from it clue to:
A.
Frictional force
B.
Centrifugal force
C.
Gravitation al force
D.
Viscous forces
Ans:
Centrifugal force
Explanation :
The extraction of cream happens because of the work of centrifugal force which works outward. The separation of cream from milk is based on the fact that when liquids of different specific gravities revolve around the same centre at the same distance with the same angular velocity, a greater centrifugal force is exerted on the heavier liquid than on the lighter one. Milk can be regarded as two liquids of different specific gravities, the serum and the fat.
[19] Moving electric charge produces -
A.
magnetic field
B.
sound waves
C.
light rays
D.
heat waves
Ans:
magnetic field
Explanation :
An electric charge always produces an electric field, regardless of speed, and a moving charge generates a magnetic field. An electric current passing through a conductor produces a magnetic field because it has many charges in motion.
[20] The process of union of two or more molecules of a substance to form a large single molecule is called :
A.
Fusion
B.
Diffusion
C.
Polymerization
D.
Synthesis
Ans:
Polymerization
Explanation :
Polymerisation is the chemical process of monomers joining together to form polymers, often it takes many thousands of monomers to make a single polymer.
[21] When a barometer reading suddenly recedes, it indicates that climate –
A.
will be very warm
B.
will be extremely stormy
C.
will remain cold
D.
incessant rain for at least 48 hours
Ans:
will be extremely stormy
Explanation :
In summer, when the barometer falls suddenly, a thunderstorm can be expected, and if it does not rise again upon its cessation, the weather will probably continue unsettled for several days. In summer, when a thunderstorm happens, there is little or no depression of the barometer.
[22] Which colour of light shows maximum deviation when passed through a prism?
A.
White
B.
Red
C.
Violet
D.
Green
Ans:
Violet
Explanation :
The angle of deviation, by which the light of a particular wavelength gets deviated on passing through a medium, depends upon the refractive index of the medium, as encountered by that light wavelength. The smaller the wavelength of the passing light, the greater is the refractive index observed.
[23] The best material for the core of a transformer is –
A.
stainless steel
B.
mild steel
C.
hard steel
D.
soft iron
Ans:
soft iron
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
As per the norm, the permissible noise level in residential areas is 45 db during night time, 55 db during day and in commercial areas it is 55 db during night and 65 db during day.
[18] When milk is churned, the cream separates from it clue to:
A.
Frictional force
B.
Centrifugal force
C.
Gravitation al force
D.
Viscous forces
Ans:
Centrifugal force
Explanation :
The extraction of cream happens because of the work of centrifugal force which works outward. The separation of cream from milk is based on the fact that when liquids of different specific gravities revolve around the same centre at the same distance with the same angular velocity, a greater centrifugal force is exerted on the heavier liquid than on the lighter one. Milk can be regarded as two liquids of different specific gravities, the serum and the fat.
[19] Moving electric charge produces -
A.
magnetic field
B.
sound waves
C.
light rays
D.
heat waves
Ans:
magnetic field
Explanation :
An electric charge always produces an electric field, regardless of speed, and a moving charge generates a magnetic field. An electric current passing through a conductor produces a magnetic field because it has many charges in motion.
[20] The process of union of two or more molecules of a substance to form a large single molecule is called :
A.
Fusion
B.
Diffusion
C.
Polymerization
D.
Synthesis
Ans:
Polymerization
Explanation :
Polymerisation is the chemical process of monomers joining together to form polymers, often it takes many thousands of monomers to make a single polymer.
[21] When a barometer reading suddenly recedes, it indicates that climate –
A.
will be very warm
B.
will be extremely stormy
C.
will remain cold
D.
incessant rain for at least 48 hours
Ans:
will be extremely stormy
Explanation :
In summer, when the barometer falls suddenly, a thunderstorm can be expected, and if it does not rise again upon its cessation, the weather will probably continue unsettled for several days. In summer, when a thunderstorm happens, there is little or no depression of the barometer.
[22] Which colour of light shows maximum deviation when passed through a prism?
A.
White
B.
Red
C.
Violet
D.
Green
Ans:
Violet
Explanation :
The angle of deviation, by which the light of a particular wavelength gets deviated on passing through a medium, depends upon the refractive index of the medium, as encountered by that light wavelength. The smaller the wavelength of the passing light, the greater is the refractive index observed.
[23] The best material for the core of a transformer is –
A.
stainless steel
B.
mild steel
C.
hard steel
D.
soft iron
Ans:
soft iron
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
An electric charge always produces an electric field, regardless of speed, and a moving charge generates a magnetic field. An electric current passing through a conductor produces a magnetic field because it has many charges in motion.
[20] The process of union of two or more molecules of a substance to form a large single molecule is called :
A.
Fusion
B.
Diffusion
C.
Polymerization
D.
Synthesis
Ans:
Polymerization
Explanation :
Polymerisation is the chemical process of monomers joining together to form polymers, often it takes many thousands of monomers to make a single polymer.
[21] When a barometer reading suddenly recedes, it indicates that climate –
A.
will be very warm
B.
will be extremely stormy
C.
will remain cold
D.
incessant rain for at least 48 hours
Ans:
will be extremely stormy
Explanation :
In summer, when the barometer falls suddenly, a thunderstorm can be expected, and if it does not rise again upon its cessation, the weather will probably continue unsettled for several days. In summer, when a thunderstorm happens, there is little or no depression of the barometer.
[22] Which colour of light shows maximum deviation when passed through a prism?
A.
White
B.
Red
C.
Violet
D.
Green
Ans:
Violet
Explanation :
The angle of deviation, by which the light of a particular wavelength gets deviated on passing through a medium, depends upon the refractive index of the medium, as encountered by that light wavelength. The smaller the wavelength of the passing light, the greater is the refractive index observed.
[23] The best material for the core of a transformer is –
A.
stainless steel
B.
mild steel
C.
hard steel
D.
soft iron
Ans:
soft iron
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
In summer, when the barometer falls suddenly, a thunderstorm can be expected, and if it does not rise again upon its cessation, the weather will probably continue unsettled for several days. In summer, when a thunderstorm happens, there is little or no depression of the barometer.
[22] Which colour of light shows maximum deviation when passed through a prism?
A.
White
B.
Red
C.
Violet
D.
Green
Ans:
Violet
Explanation :
The angle of deviation, by which the light of a particular wavelength gets deviated on passing through a medium, depends upon the refractive index of the medium, as encountered by that light wavelength. The smaller the wavelength of the passing light, the greater is the refractive index observed.
[23] The best material for the core of a transformer is –
A.
stainless steel
B.
mild steel
C.
hard steel
D.
soft iron
Ans:
soft iron
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
Iron has a very large magnetic response: it greatly amplifies an applied magnetic field. The transformer's ability to transfer energy depends on the strength of the magnetic field, so it is very helpful if the field is amplified. The input energy can then be lower while still having the same effect.
[24] Electron microscope was invented by –
A.
Knoll and Ruska
B.
Robert. Koch
C.
Lecuwenhock
D.
C.P. Swanson
Ans:
Knoll and Ruska
Explanation :
It is widely accepted that the first prototype of an electron microscope was built by Ernst Ruska and Max Knoll in 1931; it was not more powerful than an optical microscope, but it demonstrated the principle that is still used in today's sophisticated and powerful instruments, and earned its builders a share of a Nobel Prize. An electron microscope uses a beam of electrons to illuminate a specimen and produce a magnified image.
[25] Hydrogen bomb is based on the principle of -
A.
Double decomposition
B.
Artificial radioactivity
C.
Nuclear fission
D.
Nuclear fusion
Ans:
Nuclear fusion
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.
Explanation :
Hydrogen Bomb is based on the principle of Nuclear Fusion. Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.