[1] Water cannot be used to extinguish fire caused by electric current, because –
A.
it may cause electrocution
B.
it may cause hydrolysis
C.
it may cause electrolysis
D.
it may spoil the wiring
Ans:
it may cause electrocution
Explanation :
Using water for putting out electric fires is risky, as the firemen can be electrocuted by the water jet. Water is a good conductor of electricity, and, the electric current flows through the water jet directly into the hands of the person who is holding the water-hose, resulting in immediate electrocution
[2] The radiation initially produced in fluorescent tube is –
A.
infrared
B.
ultraviolet
C.
microwaves
D.
X-rays
Ans:
ultraviolet
Explanation :
The primary radiation that is initially produced within a fluorescent lamp is analogous to that emitted by a low pressure mercury lamp. Fluorescent lamps produce UV radiation by ionizing low-pressure mercury vapour. A phosphorescent coating on the inside of the tubes absorbs the UV and converts it to visible light.
[3] The 'four stroke petrol engine' is based on –
A.
Carnot-cycle
B.
Otto-cycle
C.
Diesel-cycle
D.
Boyle's-cycle
Ans:
Otto-cycle
Explanation :
A four-stroke engine (also known as four-cycle) is an internal combustion engine in which the piston completes four separate strokes—intake, compression, power, and exhaust—during two separate revolutions of the engine's crankshaft, and one single thermodynamic cycle.
[4] The device which transfer the signal from low resistance region to high resistance region is –
A.
diode
B.
transistor
C.
capacitor
D.
inductor
Ans:
transistor
Explanation :
A transistor transfers a signal from a low resistance to high resistance. It has two PN-junctions: one junction is forward biased and other junction is reverse biased having low resistance path and high resistance path respectively. The weak signal is introduced in the low resistance, circuit and output is taken from the high resistance circuit.
[5] A rubber ball is dropped from a height of 2 metres. To what height will it rise if there is no loss of energy/velocity after rebounding?
A.
4 metres
B.
3 metres
C.
2 metres
D.
1 metre
Ans:
2 metres
Explanation :
The potential energy of a body when raised through height h is given by mgh. Each time, a normal rubber ball hits the floor, it loses one-fifth of its total energy and the rebound height is proportional to energy, so each bounce will rebound to four-fifth of the previous bounce. But, the question states that there is no loss of energy/velocity after rebounding. So the height of 2 metres will be maintained.
[6] The atmospheric air is held to the Earth by –
A.
gravity
B.
winds
C.
clouds
D.
rotation of the Earth
Ans:
gravity
Explanation :
The atmosphere is an ocean of air held in place by gravity, extending from the surface to an altitude of hundreds of kilometers, the edge of space. Energy from the sun heating the air and land surface to different degrees, drives atmospheric circulation.
[7] In which of the following processes is energy released?
A.
Respiration
B.
Photosynthesis
C.
Ingestion
D.
Absorption
Ans:
Respiration
Explanation :
Cellular respiration is the set of the metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products. The reactions involved in respiration are catabolic reactions, which break large molecules into smaller ones, releasing energy in the process as they break high-energy bonds.
[8] Atomic power plant works on the principle of –
A.
Fission
B.
Fusion
C.
Thermal combustion
D.
Combined effect of all the above three
Ans:
Fission
Explanation :
A nuclear power plant is a facility at which energy released by the fissioning of atoms is converted to electrical energy under strictly regulated operating conditions. The major processes are the same as those in nonnuclear (conventional) power plants except that the coal or oil fired boiler is replaced by a nuclear reactor.
[9] Which of the following circuit elements is used to 'block' DC in an electronic circuit?
A.
Resistances
B.
Capacitance
C.
Inductance
D.
Diode
Ans:
Capacitance
Explanation :
A capacitor (originally known as condenser) is a passive two-terminal electrical component used to store energy in an electric field. Capacitors are widely used in electronic circuits for blocking direct current while allowing alternating current to pass, in filter networks, for smoothing the output of power supplies, in the resonant circuits that tune radios to particular frequencies, in electric power transmission systems for stabilizing voltage and power flow, and for many other purposes.
[10] Spectacles used for viewing 3D films have –
A.
Bifocal lens
B.
Convex lens
C.
Concave lens
D.
Polaroid
Ans:
Polaroid
Explanation :
A polarized 3D system uses polarization glasses to create the illusion of three-dimensional images by restricting the light that reaches each eye, an example of stereoscopy. To present stereoscopic images and films, two images are projected superimposed onto the same screen or display through different polarizing filters. The viewer wears low-cost eyeglasses which contain a pair of different polarizing filters. As each filter passes only that light which is similarly polarized and blocks the light polarized in the opposite direction, each eye sees a different image.
[11] Which of the following has got more heat capacity?
A.
Iron piece
B.
Water
C.
Gold piece
D.
Benzene
Ans:
Water
Explanation :
Heat capacity (usually denoted by a capital C, often with subscripts), or thermal capacity, is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount. In the International System of Units (SI), heat capacity is expressed in units of joule(s) (J) per Kelvin (K).
[12] Which of the following statements is true when we see 'rainbow'?
A.
We face sun and raindrops
B.
The Sun remains behind us and we face raindrops
C.
In light rainfall, we face Sun
D.
The sky remains clear and the sun is at lower position in the sky
Ans:
The Sun remains behind us and we face raindrops
Explanation :
We see rainbows because of the geometry of raindrops. When the sun shines from behind us into the rain, incident rays of light enter the drop and are refracted inwards. They are reflected from the back surface of the raindrop, and refracted again as they exit the raindrop and return to our eyes. A rainbow is an optical and meteorological phenomenon that is caused by reflection of light in water droplets in the Earth's atmosphere, resulting in a spectrum of light appearing in the sky.
[13] If the temperature of a place increases suddenly, the relative humidity –
A.
Increases
B.
Decreases
C.
Remains constant
D.
Fluctuates
Ans:
Decreases
Explanation :
Relative humidity is the ratio of the partial pressure of water vapor in an air-water mixture to the saturated vapor pressure of water at a prescribed temperature. The relative humidity of air depends not only on temperature but also on the pressure of the system of interest. If the system at State A is isobarically heated (heating with no change in system pressure) then the relative humidity of the system decreases because the saturated vapor pressure of water increases with increasing temperature.
[14] Pulsars are :
A.
stars moving towards the Earth
B.
stars moving away from Earth
C.
rapidly spinning stars
D.
high temperature stars
Ans:
rapidly spinning stars
Explanation :
Pulsars are celestial objects, thought to be rapidly spinning stars, that emits regular pulses of radio waves and other electromagnetic radiation at the rate of upto one thousand pulses per second.
[15] Tungsten is used for the manufacture of the filament of an electric bulb, because –
A.
It is a good conductor
B.
It is economical
C.
It is malleable
D.
It has a very high melting point
Ans:
It has a very high melting point
Explanation :
Tungsten is used because it has the highest melting point of all the metallic elements. It melts at 3410 degrees Celsius. When current passes through the filament it heats it up. When the filament reaches a certain temperature it starts to give off light, that's how we get a light bulb. The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo).
[16] What is the wavelength of visible spectrum?
A.
1300 A° -3000 A°
B.
3900 A° - 7600 A°
C.
7800 A° - 8000 A°
D.
8500 A° - 9800 A°
Ans:
3900 A° - 7600 A°
Explanation :
The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 750 nm in terms of angstrom it is in between 3900 - 7600 A°.
[17] The shape of our Milky Way galaxy is –
A.
circular
B.
elliptical
C.
spiral
D.
None of the above
Ans:
spiral
Explanation :
The Milky Way is a barred spiral galaxy 100,000-120,000 light-years in diameter containing 200-400 billion stars. It may contain at least as many planets, with an estimated 10 billion of those orbiting in the habitable zone of their parent stars. The Milky Way is the galaxy that contains our Solar System. This name derives from its appearance as a dim "milky" glowing band arching across the night sky, in which the naked eye cannot distinguish individual stars.
[18] The different colours of different stars are due to the variation of –
A.
temperature
B.
pressure
C.
density
D.
radiation from them
Ans:
temperature
Explanation :
Shortly after blackbody radiation was understood, it was noticed that the spectra of stars look extremely similar to blackbody radiation curves of various temperatures, ranging from a few thousand Kelvin to ~50,000 Kelvin. The obvious conclusion is that stars are similar to blackbodies, and that the colour variation of stars is a direct consequence of their surface temperatures.
[19] The splitting of different colours of light in a prism is :
A.
Reflection of light
B.
Dispersion light
C.
Diffraction light
D.
Refraction of light
Ans:
Dispersion light
Explanation :
The refractive index of many materials (such as glass) varies with the wavelength or colour of the light used, a phenomenon known as dispersion. This causes light of different colours to be refracted differently and to leave the prism at different angles, creating an effect similar to a rainbow. In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency, or alternatively when the group velocity depends on the frequency.
[20] A boat will submerge when it displaces water equal to its own:
A.
volume
B.
weight
C.
surface area
D.
density
Ans:
weight
Explanation :
A boat will float when the weight of the water it displaces equals the weight of the boat and anything will float if it is shaped to displace its own weight of water before it reaches the point where it will submerge. Floating of the boat works on the principle of buoyancy force which is an upward force exerted by a liquid, gas or other fluid, that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.
[21] Anemometer is used to measure –
A.
wind direction
B.
wind velocity
C.
pressure gradient
D.
wind speed and time
Ans:
wind velocity
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The first known description of an anemometer was given by Leon Battista Alberti around 1450.
[22] Which one of the following has the highest value of specific heat?
A.
Glass
B.
Copper
C.
Lead
D.
Water
Ans:
Water
Explanation :
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C which is higher than any other common substance. As a result, water plays a very important role in temperature regulation
[23] The device used for locating submerged objects under sea is –
A.
sonar
B.
radar
C.
laser
D.
maser
Ans:
sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
Using water for putting out electric fires is risky, as the firemen can be electrocuted by the water jet. Water is a good conductor of electricity, and, the electric current flows through the water jet directly into the hands of the person who is holding the water-hose, resulting in immediate electrocution
[2] The radiation initially produced in fluorescent tube is –
A.
infrared
B.
ultraviolet
C.
microwaves
D.
X-rays
Ans:
ultraviolet
Explanation :
The primary radiation that is initially produced within a fluorescent lamp is analogous to that emitted by a low pressure mercury lamp. Fluorescent lamps produce UV radiation by ionizing low-pressure mercury vapour. A phosphorescent coating on the inside of the tubes absorbs the UV and converts it to visible light.
[3] The 'four stroke petrol engine' is based on –
A.
Carnot-cycle
B.
Otto-cycle
C.
Diesel-cycle
D.
Boyle's-cycle
Ans:
Otto-cycle
Explanation :
A four-stroke engine (also known as four-cycle) is an internal combustion engine in which the piston completes four separate strokes—intake, compression, power, and exhaust—during two separate revolutions of the engine's crankshaft, and one single thermodynamic cycle.
[4] The device which transfer the signal from low resistance region to high resistance region is –
A.
diode
B.
transistor
C.
capacitor
D.
inductor
Ans:
transistor
Explanation :
A transistor transfers a signal from a low resistance to high resistance. It has two PN-junctions: one junction is forward biased and other junction is reverse biased having low resistance path and high resistance path respectively. The weak signal is introduced in the low resistance, circuit and output is taken from the high resistance circuit.
[5] A rubber ball is dropped from a height of 2 metres. To what height will it rise if there is no loss of energy/velocity after rebounding?
A.
4 metres
B.
3 metres
C.
2 metres
D.
1 metre
Ans:
2 metres
Explanation :
The potential energy of a body when raised through height h is given by mgh. Each time, a normal rubber ball hits the floor, it loses one-fifth of its total energy and the rebound height is proportional to energy, so each bounce will rebound to four-fifth of the previous bounce. But, the question states that there is no loss of energy/velocity after rebounding. So the height of 2 metres will be maintained.
[6] The atmospheric air is held to the Earth by –
A.
gravity
B.
winds
C.
clouds
D.
rotation of the Earth
Ans:
gravity
Explanation :
The atmosphere is an ocean of air held in place by gravity, extending from the surface to an altitude of hundreds of kilometers, the edge of space. Energy from the sun heating the air and land surface to different degrees, drives atmospheric circulation.
[7] In which of the following processes is energy released?
A.
Respiration
B.
Photosynthesis
C.
Ingestion
D.
Absorption
Ans:
Respiration
Explanation :
Cellular respiration is the set of the metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products. The reactions involved in respiration are catabolic reactions, which break large molecules into smaller ones, releasing energy in the process as they break high-energy bonds.
[8] Atomic power plant works on the principle of –
A.
Fission
B.
Fusion
C.
Thermal combustion
D.
Combined effect of all the above three
Ans:
Fission
Explanation :
A nuclear power plant is a facility at which energy released by the fissioning of atoms is converted to electrical energy under strictly regulated operating conditions. The major processes are the same as those in nonnuclear (conventional) power plants except that the coal or oil fired boiler is replaced by a nuclear reactor.
[9] Which of the following circuit elements is used to 'block' DC in an electronic circuit?
A.
Resistances
B.
Capacitance
C.
Inductance
D.
Diode
Ans:
Capacitance
Explanation :
A capacitor (originally known as condenser) is a passive two-terminal electrical component used to store energy in an electric field. Capacitors are widely used in electronic circuits for blocking direct current while allowing alternating current to pass, in filter networks, for smoothing the output of power supplies, in the resonant circuits that tune radios to particular frequencies, in electric power transmission systems for stabilizing voltage and power flow, and for many other purposes.
[10] Spectacles used for viewing 3D films have –
A.
Bifocal lens
B.
Convex lens
C.
Concave lens
D.
Polaroid
Ans:
Polaroid
Explanation :
A polarized 3D system uses polarization glasses to create the illusion of three-dimensional images by restricting the light that reaches each eye, an example of stereoscopy. To present stereoscopic images and films, two images are projected superimposed onto the same screen or display through different polarizing filters. The viewer wears low-cost eyeglasses which contain a pair of different polarizing filters. As each filter passes only that light which is similarly polarized and blocks the light polarized in the opposite direction, each eye sees a different image.
[11] Which of the following has got more heat capacity?
A.
Iron piece
B.
Water
C.
Gold piece
D.
Benzene
Ans:
Water
Explanation :
Heat capacity (usually denoted by a capital C, often with subscripts), or thermal capacity, is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount. In the International System of Units (SI), heat capacity is expressed in units of joule(s) (J) per Kelvin (K).
[12] Which of the following statements is true when we see 'rainbow'?
A.
We face sun and raindrops
B.
The Sun remains behind us and we face raindrops
C.
In light rainfall, we face Sun
D.
The sky remains clear and the sun is at lower position in the sky
Ans:
The Sun remains behind us and we face raindrops
Explanation :
We see rainbows because of the geometry of raindrops. When the sun shines from behind us into the rain, incident rays of light enter the drop and are refracted inwards. They are reflected from the back surface of the raindrop, and refracted again as they exit the raindrop and return to our eyes. A rainbow is an optical and meteorological phenomenon that is caused by reflection of light in water droplets in the Earth's atmosphere, resulting in a spectrum of light appearing in the sky.
[13] If the temperature of a place increases suddenly, the relative humidity –
A.
Increases
B.
Decreases
C.
Remains constant
D.
Fluctuates
Ans:
Decreases
Explanation :
Relative humidity is the ratio of the partial pressure of water vapor in an air-water mixture to the saturated vapor pressure of water at a prescribed temperature. The relative humidity of air depends not only on temperature but also on the pressure of the system of interest. If the system at State A is isobarically heated (heating with no change in system pressure) then the relative humidity of the system decreases because the saturated vapor pressure of water increases with increasing temperature.
[14] Pulsars are :
A.
stars moving towards the Earth
B.
stars moving away from Earth
C.
rapidly spinning stars
D.
high temperature stars
Ans:
rapidly spinning stars
Explanation :
Pulsars are celestial objects, thought to be rapidly spinning stars, that emits regular pulses of radio waves and other electromagnetic radiation at the rate of upto one thousand pulses per second.
[15] Tungsten is used for the manufacture of the filament of an electric bulb, because –
A.
It is a good conductor
B.
It is economical
C.
It is malleable
D.
It has a very high melting point
Ans:
It has a very high melting point
Explanation :
Tungsten is used because it has the highest melting point of all the metallic elements. It melts at 3410 degrees Celsius. When current passes through the filament it heats it up. When the filament reaches a certain temperature it starts to give off light, that's how we get a light bulb. The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo).
[16] What is the wavelength of visible spectrum?
A.
1300 A° -3000 A°
B.
3900 A° - 7600 A°
C.
7800 A° - 8000 A°
D.
8500 A° - 9800 A°
Ans:
3900 A° - 7600 A°
Explanation :
The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 750 nm in terms of angstrom it is in between 3900 - 7600 A°.
[17] The shape of our Milky Way galaxy is –
A.
circular
B.
elliptical
C.
spiral
D.
None of the above
Ans:
spiral
Explanation :
The Milky Way is a barred spiral galaxy 100,000-120,000 light-years in diameter containing 200-400 billion stars. It may contain at least as many planets, with an estimated 10 billion of those orbiting in the habitable zone of their parent stars. The Milky Way is the galaxy that contains our Solar System. This name derives from its appearance as a dim "milky" glowing band arching across the night sky, in which the naked eye cannot distinguish individual stars.
[18] The different colours of different stars are due to the variation of –
A.
temperature
B.
pressure
C.
density
D.
radiation from them
Ans:
temperature
Explanation :
Shortly after blackbody radiation was understood, it was noticed that the spectra of stars look extremely similar to blackbody radiation curves of various temperatures, ranging from a few thousand Kelvin to ~50,000 Kelvin. The obvious conclusion is that stars are similar to blackbodies, and that the colour variation of stars is a direct consequence of their surface temperatures.
[19] The splitting of different colours of light in a prism is :
A.
Reflection of light
B.
Dispersion light
C.
Diffraction light
D.
Refraction of light
Ans:
Dispersion light
Explanation :
The refractive index of many materials (such as glass) varies with the wavelength or colour of the light used, a phenomenon known as dispersion. This causes light of different colours to be refracted differently and to leave the prism at different angles, creating an effect similar to a rainbow. In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency, or alternatively when the group velocity depends on the frequency.
[20] A boat will submerge when it displaces water equal to its own:
A.
volume
B.
weight
C.
surface area
D.
density
Ans:
weight
Explanation :
A boat will float when the weight of the water it displaces equals the weight of the boat and anything will float if it is shaped to displace its own weight of water before it reaches the point where it will submerge. Floating of the boat works on the principle of buoyancy force which is an upward force exerted by a liquid, gas or other fluid, that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.
[21] Anemometer is used to measure –
A.
wind direction
B.
wind velocity
C.
pressure gradient
D.
wind speed and time
Ans:
wind velocity
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The first known description of an anemometer was given by Leon Battista Alberti around 1450.
[22] Which one of the following has the highest value of specific heat?
A.
Glass
B.
Copper
C.
Lead
D.
Water
Ans:
Water
Explanation :
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C which is higher than any other common substance. As a result, water plays a very important role in temperature regulation
[23] The device used for locating submerged objects under sea is –
A.
sonar
B.
radar
C.
laser
D.
maser
Ans:
sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
A four-stroke engine (also known as four-cycle) is an internal combustion engine in which the piston completes four separate strokes—intake, compression, power, and exhaust—during two separate revolutions of the engine's crankshaft, and one single thermodynamic cycle.
[4] The device which transfer the signal from low resistance region to high resistance region is –
A.
diode
B.
transistor
C.
capacitor
D.
inductor
Ans:
transistor
Explanation :
A transistor transfers a signal from a low resistance to high resistance. It has two PN-junctions: one junction is forward biased and other junction is reverse biased having low resistance path and high resistance path respectively. The weak signal is introduced in the low resistance, circuit and output is taken from the high resistance circuit.
[5] A rubber ball is dropped from a height of 2 metres. To what height will it rise if there is no loss of energy/velocity after rebounding?
A.
4 metres
B.
3 metres
C.
2 metres
D.
1 metre
Ans:
2 metres
Explanation :
The potential energy of a body when raised through height h is given by mgh. Each time, a normal rubber ball hits the floor, it loses one-fifth of its total energy and the rebound height is proportional to energy, so each bounce will rebound to four-fifth of the previous bounce. But, the question states that there is no loss of energy/velocity after rebounding. So the height of 2 metres will be maintained.
[6] The atmospheric air is held to the Earth by –
A.
gravity
B.
winds
C.
clouds
D.
rotation of the Earth
Ans:
gravity
Explanation :
The atmosphere is an ocean of air held in place by gravity, extending from the surface to an altitude of hundreds of kilometers, the edge of space. Energy from the sun heating the air and land surface to different degrees, drives atmospheric circulation.
[7] In which of the following processes is energy released?
A.
Respiration
B.
Photosynthesis
C.
Ingestion
D.
Absorption
Ans:
Respiration
Explanation :
Cellular respiration is the set of the metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products. The reactions involved in respiration are catabolic reactions, which break large molecules into smaller ones, releasing energy in the process as they break high-energy bonds.
[8] Atomic power plant works on the principle of –
A.
Fission
B.
Fusion
C.
Thermal combustion
D.
Combined effect of all the above three
Ans:
Fission
Explanation :
A nuclear power plant is a facility at which energy released by the fissioning of atoms is converted to electrical energy under strictly regulated operating conditions. The major processes are the same as those in nonnuclear (conventional) power plants except that the coal or oil fired boiler is replaced by a nuclear reactor.
[9] Which of the following circuit elements is used to 'block' DC in an electronic circuit?
A.
Resistances
B.
Capacitance
C.
Inductance
D.
Diode
Ans:
Capacitance
Explanation :
A capacitor (originally known as condenser) is a passive two-terminal electrical component used to store energy in an electric field. Capacitors are widely used in electronic circuits for blocking direct current while allowing alternating current to pass, in filter networks, for smoothing the output of power supplies, in the resonant circuits that tune radios to particular frequencies, in electric power transmission systems for stabilizing voltage and power flow, and for many other purposes.
[10] Spectacles used for viewing 3D films have –
A.
Bifocal lens
B.
Convex lens
C.
Concave lens
D.
Polaroid
Ans:
Polaroid
Explanation :
A polarized 3D system uses polarization glasses to create the illusion of three-dimensional images by restricting the light that reaches each eye, an example of stereoscopy. To present stereoscopic images and films, two images are projected superimposed onto the same screen or display through different polarizing filters. The viewer wears low-cost eyeglasses which contain a pair of different polarizing filters. As each filter passes only that light which is similarly polarized and blocks the light polarized in the opposite direction, each eye sees a different image.
[11] Which of the following has got more heat capacity?
A.
Iron piece
B.
Water
C.
Gold piece
D.
Benzene
Ans:
Water
Explanation :
Heat capacity (usually denoted by a capital C, often with subscripts), or thermal capacity, is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount. In the International System of Units (SI), heat capacity is expressed in units of joule(s) (J) per Kelvin (K).
[12] Which of the following statements is true when we see 'rainbow'?
A.
We face sun and raindrops
B.
The Sun remains behind us and we face raindrops
C.
In light rainfall, we face Sun
D.
The sky remains clear and the sun is at lower position in the sky
Ans:
The Sun remains behind us and we face raindrops
Explanation :
We see rainbows because of the geometry of raindrops. When the sun shines from behind us into the rain, incident rays of light enter the drop and are refracted inwards. They are reflected from the back surface of the raindrop, and refracted again as they exit the raindrop and return to our eyes. A rainbow is an optical and meteorological phenomenon that is caused by reflection of light in water droplets in the Earth's atmosphere, resulting in a spectrum of light appearing in the sky.
[13] If the temperature of a place increases suddenly, the relative humidity –
A.
Increases
B.
Decreases
C.
Remains constant
D.
Fluctuates
Ans:
Decreases
Explanation :
Relative humidity is the ratio of the partial pressure of water vapor in an air-water mixture to the saturated vapor pressure of water at a prescribed temperature. The relative humidity of air depends not only on temperature but also on the pressure of the system of interest. If the system at State A is isobarically heated (heating with no change in system pressure) then the relative humidity of the system decreases because the saturated vapor pressure of water increases with increasing temperature.
[14] Pulsars are :
A.
stars moving towards the Earth
B.
stars moving away from Earth
C.
rapidly spinning stars
D.
high temperature stars
Ans:
rapidly spinning stars
Explanation :
Pulsars are celestial objects, thought to be rapidly spinning stars, that emits regular pulses of radio waves and other electromagnetic radiation at the rate of upto one thousand pulses per second.
[15] Tungsten is used for the manufacture of the filament of an electric bulb, because –
A.
It is a good conductor
B.
It is economical
C.
It is malleable
D.
It has a very high melting point
Ans:
It has a very high melting point
Explanation :
Tungsten is used because it has the highest melting point of all the metallic elements. It melts at 3410 degrees Celsius. When current passes through the filament it heats it up. When the filament reaches a certain temperature it starts to give off light, that's how we get a light bulb. The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo).
[16] What is the wavelength of visible spectrum?
A.
1300 A° -3000 A°
B.
3900 A° - 7600 A°
C.
7800 A° - 8000 A°
D.
8500 A° - 9800 A°
Ans:
3900 A° - 7600 A°
Explanation :
The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 750 nm in terms of angstrom it is in between 3900 - 7600 A°.
[17] The shape of our Milky Way galaxy is –
A.
circular
B.
elliptical
C.
spiral
D.
None of the above
Ans:
spiral
Explanation :
The Milky Way is a barred spiral galaxy 100,000-120,000 light-years in diameter containing 200-400 billion stars. It may contain at least as many planets, with an estimated 10 billion of those orbiting in the habitable zone of their parent stars. The Milky Way is the galaxy that contains our Solar System. This name derives from its appearance as a dim "milky" glowing band arching across the night sky, in which the naked eye cannot distinguish individual stars.
[18] The different colours of different stars are due to the variation of –
A.
temperature
B.
pressure
C.
density
D.
radiation from them
Ans:
temperature
Explanation :
Shortly after blackbody radiation was understood, it was noticed that the spectra of stars look extremely similar to blackbody radiation curves of various temperatures, ranging from a few thousand Kelvin to ~50,000 Kelvin. The obvious conclusion is that stars are similar to blackbodies, and that the colour variation of stars is a direct consequence of their surface temperatures.
[19] The splitting of different colours of light in a prism is :
A.
Reflection of light
B.
Dispersion light
C.
Diffraction light
D.
Refraction of light
Ans:
Dispersion light
Explanation :
The refractive index of many materials (such as glass) varies with the wavelength or colour of the light used, a phenomenon known as dispersion. This causes light of different colours to be refracted differently and to leave the prism at different angles, creating an effect similar to a rainbow. In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency, or alternatively when the group velocity depends on the frequency.
[20] A boat will submerge when it displaces water equal to its own:
A.
volume
B.
weight
C.
surface area
D.
density
Ans:
weight
Explanation :
A boat will float when the weight of the water it displaces equals the weight of the boat and anything will float if it is shaped to displace its own weight of water before it reaches the point where it will submerge. Floating of the boat works on the principle of buoyancy force which is an upward force exerted by a liquid, gas or other fluid, that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.
[21] Anemometer is used to measure –
A.
wind direction
B.
wind velocity
C.
pressure gradient
D.
wind speed and time
Ans:
wind velocity
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The first known description of an anemometer was given by Leon Battista Alberti around 1450.
[22] Which one of the following has the highest value of specific heat?
A.
Glass
B.
Copper
C.
Lead
D.
Water
Ans:
Water
Explanation :
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C which is higher than any other common substance. As a result, water plays a very important role in temperature regulation
[23] The device used for locating submerged objects under sea is –
A.
sonar
B.
radar
C.
laser
D.
maser
Ans:
sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
The potential energy of a body when raised through height h is given by mgh. Each time, a normal rubber ball hits the floor, it loses one-fifth of its total energy and the rebound height is proportional to energy, so each bounce will rebound to four-fifth of the previous bounce. But, the question states that there is no loss of energy/velocity after rebounding. So the height of 2 metres will be maintained.
[6] The atmospheric air is held to the Earth by –
A.
gravity
B.
winds
C.
clouds
D.
rotation of the Earth
Ans:
gravity
Explanation :
The atmosphere is an ocean of air held in place by gravity, extending from the surface to an altitude of hundreds of kilometers, the edge of space. Energy from the sun heating the air and land surface to different degrees, drives atmospheric circulation.
[7] In which of the following processes is energy released?
A.
Respiration
B.
Photosynthesis
C.
Ingestion
D.
Absorption
Ans:
Respiration
Explanation :
Cellular respiration is the set of the metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products. The reactions involved in respiration are catabolic reactions, which break large molecules into smaller ones, releasing energy in the process as they break high-energy bonds.
[8] Atomic power plant works on the principle of –
A.
Fission
B.
Fusion
C.
Thermal combustion
D.
Combined effect of all the above three
Ans:
Fission
Explanation :
A nuclear power plant is a facility at which energy released by the fissioning of atoms is converted to electrical energy under strictly regulated operating conditions. The major processes are the same as those in nonnuclear (conventional) power plants except that the coal or oil fired boiler is replaced by a nuclear reactor.
[9] Which of the following circuit elements is used to 'block' DC in an electronic circuit?
A.
Resistances
B.
Capacitance
C.
Inductance
D.
Diode
Ans:
Capacitance
Explanation :
A capacitor (originally known as condenser) is a passive two-terminal electrical component used to store energy in an electric field. Capacitors are widely used in electronic circuits for blocking direct current while allowing alternating current to pass, in filter networks, for smoothing the output of power supplies, in the resonant circuits that tune radios to particular frequencies, in electric power transmission systems for stabilizing voltage and power flow, and for many other purposes.
[10] Spectacles used for viewing 3D films have –
A.
Bifocal lens
B.
Convex lens
C.
Concave lens
D.
Polaroid
Ans:
Polaroid
Explanation :
A polarized 3D system uses polarization glasses to create the illusion of three-dimensional images by restricting the light that reaches each eye, an example of stereoscopy. To present stereoscopic images and films, two images are projected superimposed onto the same screen or display through different polarizing filters. The viewer wears low-cost eyeglasses which contain a pair of different polarizing filters. As each filter passes only that light which is similarly polarized and blocks the light polarized in the opposite direction, each eye sees a different image.
[11] Which of the following has got more heat capacity?
A.
Iron piece
B.
Water
C.
Gold piece
D.
Benzene
Ans:
Water
Explanation :
Heat capacity (usually denoted by a capital C, often with subscripts), or thermal capacity, is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount. In the International System of Units (SI), heat capacity is expressed in units of joule(s) (J) per Kelvin (K).
[12] Which of the following statements is true when we see 'rainbow'?
A.
We face sun and raindrops
B.
The Sun remains behind us and we face raindrops
C.
In light rainfall, we face Sun
D.
The sky remains clear and the sun is at lower position in the sky
Ans:
The Sun remains behind us and we face raindrops
Explanation :
We see rainbows because of the geometry of raindrops. When the sun shines from behind us into the rain, incident rays of light enter the drop and are refracted inwards. They are reflected from the back surface of the raindrop, and refracted again as they exit the raindrop and return to our eyes. A rainbow is an optical and meteorological phenomenon that is caused by reflection of light in water droplets in the Earth's atmosphere, resulting in a spectrum of light appearing in the sky.
[13] If the temperature of a place increases suddenly, the relative humidity –
A.
Increases
B.
Decreases
C.
Remains constant
D.
Fluctuates
Ans:
Decreases
Explanation :
Relative humidity is the ratio of the partial pressure of water vapor in an air-water mixture to the saturated vapor pressure of water at a prescribed temperature. The relative humidity of air depends not only on temperature but also on the pressure of the system of interest. If the system at State A is isobarically heated (heating with no change in system pressure) then the relative humidity of the system decreases because the saturated vapor pressure of water increases with increasing temperature.
[14] Pulsars are :
A.
stars moving towards the Earth
B.
stars moving away from Earth
C.
rapidly spinning stars
D.
high temperature stars
Ans:
rapidly spinning stars
Explanation :
Pulsars are celestial objects, thought to be rapidly spinning stars, that emits regular pulses of radio waves and other electromagnetic radiation at the rate of upto one thousand pulses per second.
[15] Tungsten is used for the manufacture of the filament of an electric bulb, because –
A.
It is a good conductor
B.
It is economical
C.
It is malleable
D.
It has a very high melting point
Ans:
It has a very high melting point
Explanation :
Tungsten is used because it has the highest melting point of all the metallic elements. It melts at 3410 degrees Celsius. When current passes through the filament it heats it up. When the filament reaches a certain temperature it starts to give off light, that's how we get a light bulb. The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo).
[16] What is the wavelength of visible spectrum?
A.
1300 A° -3000 A°
B.
3900 A° - 7600 A°
C.
7800 A° - 8000 A°
D.
8500 A° - 9800 A°
Ans:
3900 A° - 7600 A°
Explanation :
The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 750 nm in terms of angstrom it is in between 3900 - 7600 A°.
[17] The shape of our Milky Way galaxy is –
A.
circular
B.
elliptical
C.
spiral
D.
None of the above
Ans:
spiral
Explanation :
The Milky Way is a barred spiral galaxy 100,000-120,000 light-years in diameter containing 200-400 billion stars. It may contain at least as many planets, with an estimated 10 billion of those orbiting in the habitable zone of their parent stars. The Milky Way is the galaxy that contains our Solar System. This name derives from its appearance as a dim "milky" glowing band arching across the night sky, in which the naked eye cannot distinguish individual stars.
[18] The different colours of different stars are due to the variation of –
A.
temperature
B.
pressure
C.
density
D.
radiation from them
Ans:
temperature
Explanation :
Shortly after blackbody radiation was understood, it was noticed that the spectra of stars look extremely similar to blackbody radiation curves of various temperatures, ranging from a few thousand Kelvin to ~50,000 Kelvin. The obvious conclusion is that stars are similar to blackbodies, and that the colour variation of stars is a direct consequence of their surface temperatures.
[19] The splitting of different colours of light in a prism is :
A.
Reflection of light
B.
Dispersion light
C.
Diffraction light
D.
Refraction of light
Ans:
Dispersion light
Explanation :
The refractive index of many materials (such as glass) varies with the wavelength or colour of the light used, a phenomenon known as dispersion. This causes light of different colours to be refracted differently and to leave the prism at different angles, creating an effect similar to a rainbow. In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency, or alternatively when the group velocity depends on the frequency.
[20] A boat will submerge when it displaces water equal to its own:
A.
volume
B.
weight
C.
surface area
D.
density
Ans:
weight
Explanation :
A boat will float when the weight of the water it displaces equals the weight of the boat and anything will float if it is shaped to displace its own weight of water before it reaches the point where it will submerge. Floating of the boat works on the principle of buoyancy force which is an upward force exerted by a liquid, gas or other fluid, that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.
[21] Anemometer is used to measure –
A.
wind direction
B.
wind velocity
C.
pressure gradient
D.
wind speed and time
Ans:
wind velocity
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The first known description of an anemometer was given by Leon Battista Alberti around 1450.
[22] Which one of the following has the highest value of specific heat?
A.
Glass
B.
Copper
C.
Lead
D.
Water
Ans:
Water
Explanation :
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C which is higher than any other common substance. As a result, water plays a very important role in temperature regulation
[23] The device used for locating submerged objects under sea is –
A.
sonar
B.
radar
C.
laser
D.
maser
Ans:
sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
Cellular respiration is the set of the metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products. The reactions involved in respiration are catabolic reactions, which break large molecules into smaller ones, releasing energy in the process as they break high-energy bonds.
[8] Atomic power plant works on the principle of –
A.
Fission
B.
Fusion
C.
Thermal combustion
D.
Combined effect of all the above three
Ans:
Fission
Explanation :
A nuclear power plant is a facility at which energy released by the fissioning of atoms is converted to electrical energy under strictly regulated operating conditions. The major processes are the same as those in nonnuclear (conventional) power plants except that the coal or oil fired boiler is replaced by a nuclear reactor.
[9] Which of the following circuit elements is used to 'block' DC in an electronic circuit?
A.
Resistances
B.
Capacitance
C.
Inductance
D.
Diode
Ans:
Capacitance
Explanation :
A capacitor (originally known as condenser) is a passive two-terminal electrical component used to store energy in an electric field. Capacitors are widely used in electronic circuits for blocking direct current while allowing alternating current to pass, in filter networks, for smoothing the output of power supplies, in the resonant circuits that tune radios to particular frequencies, in electric power transmission systems for stabilizing voltage and power flow, and for many other purposes.
[10] Spectacles used for viewing 3D films have –
A.
Bifocal lens
B.
Convex lens
C.
Concave lens
D.
Polaroid
Ans:
Polaroid
Explanation :
A polarized 3D system uses polarization glasses to create the illusion of three-dimensional images by restricting the light that reaches each eye, an example of stereoscopy. To present stereoscopic images and films, two images are projected superimposed onto the same screen or display through different polarizing filters. The viewer wears low-cost eyeglasses which contain a pair of different polarizing filters. As each filter passes only that light which is similarly polarized and blocks the light polarized in the opposite direction, each eye sees a different image.
[11] Which of the following has got more heat capacity?
A.
Iron piece
B.
Water
C.
Gold piece
D.
Benzene
Ans:
Water
Explanation :
Heat capacity (usually denoted by a capital C, often with subscripts), or thermal capacity, is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount. In the International System of Units (SI), heat capacity is expressed in units of joule(s) (J) per Kelvin (K).
[12] Which of the following statements is true when we see 'rainbow'?
A.
We face sun and raindrops
B.
The Sun remains behind us and we face raindrops
C.
In light rainfall, we face Sun
D.
The sky remains clear and the sun is at lower position in the sky
Ans:
The Sun remains behind us and we face raindrops
Explanation :
We see rainbows because of the geometry of raindrops. When the sun shines from behind us into the rain, incident rays of light enter the drop and are refracted inwards. They are reflected from the back surface of the raindrop, and refracted again as they exit the raindrop and return to our eyes. A rainbow is an optical and meteorological phenomenon that is caused by reflection of light in water droplets in the Earth's atmosphere, resulting in a spectrum of light appearing in the sky.
[13] If the temperature of a place increases suddenly, the relative humidity –
A.
Increases
B.
Decreases
C.
Remains constant
D.
Fluctuates
Ans:
Decreases
Explanation :
Relative humidity is the ratio of the partial pressure of water vapor in an air-water mixture to the saturated vapor pressure of water at a prescribed temperature. The relative humidity of air depends not only on temperature but also on the pressure of the system of interest. If the system at State A is isobarically heated (heating with no change in system pressure) then the relative humidity of the system decreases because the saturated vapor pressure of water increases with increasing temperature.
[14] Pulsars are :
A.
stars moving towards the Earth
B.
stars moving away from Earth
C.
rapidly spinning stars
D.
high temperature stars
Ans:
rapidly spinning stars
Explanation :
Pulsars are celestial objects, thought to be rapidly spinning stars, that emits regular pulses of radio waves and other electromagnetic radiation at the rate of upto one thousand pulses per second.
[15] Tungsten is used for the manufacture of the filament of an electric bulb, because –
A.
It is a good conductor
B.
It is economical
C.
It is malleable
D.
It has a very high melting point
Ans:
It has a very high melting point
Explanation :
Tungsten is used because it has the highest melting point of all the metallic elements. It melts at 3410 degrees Celsius. When current passes through the filament it heats it up. When the filament reaches a certain temperature it starts to give off light, that's how we get a light bulb. The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo).
[16] What is the wavelength of visible spectrum?
A.
1300 A° -3000 A°
B.
3900 A° - 7600 A°
C.
7800 A° - 8000 A°
D.
8500 A° - 9800 A°
Ans:
3900 A° - 7600 A°
Explanation :
The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 750 nm in terms of angstrom it is in between 3900 - 7600 A°.
[17] The shape of our Milky Way galaxy is –
A.
circular
B.
elliptical
C.
spiral
D.
None of the above
Ans:
spiral
Explanation :
The Milky Way is a barred spiral galaxy 100,000-120,000 light-years in diameter containing 200-400 billion stars. It may contain at least as many planets, with an estimated 10 billion of those orbiting in the habitable zone of their parent stars. The Milky Way is the galaxy that contains our Solar System. This name derives from its appearance as a dim "milky" glowing band arching across the night sky, in which the naked eye cannot distinguish individual stars.
[18] The different colours of different stars are due to the variation of –
A.
temperature
B.
pressure
C.
density
D.
radiation from them
Ans:
temperature
Explanation :
Shortly after blackbody radiation was understood, it was noticed that the spectra of stars look extremely similar to blackbody radiation curves of various temperatures, ranging from a few thousand Kelvin to ~50,000 Kelvin. The obvious conclusion is that stars are similar to blackbodies, and that the colour variation of stars is a direct consequence of their surface temperatures.
[19] The splitting of different colours of light in a prism is :
A.
Reflection of light
B.
Dispersion light
C.
Diffraction light
D.
Refraction of light
Ans:
Dispersion light
Explanation :
The refractive index of many materials (such as glass) varies with the wavelength or colour of the light used, a phenomenon known as dispersion. This causes light of different colours to be refracted differently and to leave the prism at different angles, creating an effect similar to a rainbow. In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency, or alternatively when the group velocity depends on the frequency.
[20] A boat will submerge when it displaces water equal to its own:
A.
volume
B.
weight
C.
surface area
D.
density
Ans:
weight
Explanation :
A boat will float when the weight of the water it displaces equals the weight of the boat and anything will float if it is shaped to displace its own weight of water before it reaches the point where it will submerge. Floating of the boat works on the principle of buoyancy force which is an upward force exerted by a liquid, gas or other fluid, that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.
[21] Anemometer is used to measure –
A.
wind direction
B.
wind velocity
C.
pressure gradient
D.
wind speed and time
Ans:
wind velocity
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The first known description of an anemometer was given by Leon Battista Alberti around 1450.
[22] Which one of the following has the highest value of specific heat?
A.
Glass
B.
Copper
C.
Lead
D.
Water
Ans:
Water
Explanation :
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C which is higher than any other common substance. As a result, water plays a very important role in temperature regulation
[23] The device used for locating submerged objects under sea is –
A.
sonar
B.
radar
C.
laser
D.
maser
Ans:
sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
A capacitor (originally known as condenser) is a passive two-terminal electrical component used to store energy in an electric field. Capacitors are widely used in electronic circuits for blocking direct current while allowing alternating current to pass, in filter networks, for smoothing the output of power supplies, in the resonant circuits that tune radios to particular frequencies, in electric power transmission systems for stabilizing voltage and power flow, and for many other purposes.
[10] Spectacles used for viewing 3D films have –
A.
Bifocal lens
B.
Convex lens
C.
Concave lens
D.
Polaroid
Ans:
Polaroid
Explanation :
A polarized 3D system uses polarization glasses to create the illusion of three-dimensional images by restricting the light that reaches each eye, an example of stereoscopy. To present stereoscopic images and films, two images are projected superimposed onto the same screen or display through different polarizing filters. The viewer wears low-cost eyeglasses which contain a pair of different polarizing filters. As each filter passes only that light which is similarly polarized and blocks the light polarized in the opposite direction, each eye sees a different image.
[11] Which of the following has got more heat capacity?
A.
Iron piece
B.
Water
C.
Gold piece
D.
Benzene
Ans:
Water
Explanation :
Heat capacity (usually denoted by a capital C, often with subscripts), or thermal capacity, is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount. In the International System of Units (SI), heat capacity is expressed in units of joule(s) (J) per Kelvin (K).
[12] Which of the following statements is true when we see 'rainbow'?
A.
We face sun and raindrops
B.
The Sun remains behind us and we face raindrops
C.
In light rainfall, we face Sun
D.
The sky remains clear and the sun is at lower position in the sky
Ans:
The Sun remains behind us and we face raindrops
Explanation :
We see rainbows because of the geometry of raindrops. When the sun shines from behind us into the rain, incident rays of light enter the drop and are refracted inwards. They are reflected from the back surface of the raindrop, and refracted again as they exit the raindrop and return to our eyes. A rainbow is an optical and meteorological phenomenon that is caused by reflection of light in water droplets in the Earth's atmosphere, resulting in a spectrum of light appearing in the sky.
[13] If the temperature of a place increases suddenly, the relative humidity –
A.
Increases
B.
Decreases
C.
Remains constant
D.
Fluctuates
Ans:
Decreases
Explanation :
Relative humidity is the ratio of the partial pressure of water vapor in an air-water mixture to the saturated vapor pressure of water at a prescribed temperature. The relative humidity of air depends not only on temperature but also on the pressure of the system of interest. If the system at State A is isobarically heated (heating with no change in system pressure) then the relative humidity of the system decreases because the saturated vapor pressure of water increases with increasing temperature.
[14] Pulsars are :
A.
stars moving towards the Earth
B.
stars moving away from Earth
C.
rapidly spinning stars
D.
high temperature stars
Ans:
rapidly spinning stars
Explanation :
Pulsars are celestial objects, thought to be rapidly spinning stars, that emits regular pulses of radio waves and other electromagnetic radiation at the rate of upto one thousand pulses per second.
[15] Tungsten is used for the manufacture of the filament of an electric bulb, because –
A.
It is a good conductor
B.
It is economical
C.
It is malleable
D.
It has a very high melting point
Ans:
It has a very high melting point
Explanation :
Tungsten is used because it has the highest melting point of all the metallic elements. It melts at 3410 degrees Celsius. When current passes through the filament it heats it up. When the filament reaches a certain temperature it starts to give off light, that's how we get a light bulb. The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo).
[16] What is the wavelength of visible spectrum?
A.
1300 A° -3000 A°
B.
3900 A° - 7600 A°
C.
7800 A° - 8000 A°
D.
8500 A° - 9800 A°
Ans:
3900 A° - 7600 A°
Explanation :
The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 750 nm in terms of angstrom it is in between 3900 - 7600 A°.
[17] The shape of our Milky Way galaxy is –
A.
circular
B.
elliptical
C.
spiral
D.
None of the above
Ans:
spiral
Explanation :
The Milky Way is a barred spiral galaxy 100,000-120,000 light-years in diameter containing 200-400 billion stars. It may contain at least as many planets, with an estimated 10 billion of those orbiting in the habitable zone of their parent stars. The Milky Way is the galaxy that contains our Solar System. This name derives from its appearance as a dim "milky" glowing band arching across the night sky, in which the naked eye cannot distinguish individual stars.
[18] The different colours of different stars are due to the variation of –
A.
temperature
B.
pressure
C.
density
D.
radiation from them
Ans:
temperature
Explanation :
Shortly after blackbody radiation was understood, it was noticed that the spectra of stars look extremely similar to blackbody radiation curves of various temperatures, ranging from a few thousand Kelvin to ~50,000 Kelvin. The obvious conclusion is that stars are similar to blackbodies, and that the colour variation of stars is a direct consequence of their surface temperatures.
[19] The splitting of different colours of light in a prism is :
A.
Reflection of light
B.
Dispersion light
C.
Diffraction light
D.
Refraction of light
Ans:
Dispersion light
Explanation :
The refractive index of many materials (such as glass) varies with the wavelength or colour of the light used, a phenomenon known as dispersion. This causes light of different colours to be refracted differently and to leave the prism at different angles, creating an effect similar to a rainbow. In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency, or alternatively when the group velocity depends on the frequency.
[20] A boat will submerge when it displaces water equal to its own:
A.
volume
B.
weight
C.
surface area
D.
density
Ans:
weight
Explanation :
A boat will float when the weight of the water it displaces equals the weight of the boat and anything will float if it is shaped to displace its own weight of water before it reaches the point where it will submerge. Floating of the boat works on the principle of buoyancy force which is an upward force exerted by a liquid, gas or other fluid, that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.
[21] Anemometer is used to measure –
A.
wind direction
B.
wind velocity
C.
pressure gradient
D.
wind speed and time
Ans:
wind velocity
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The first known description of an anemometer was given by Leon Battista Alberti around 1450.
[22] Which one of the following has the highest value of specific heat?
A.
Glass
B.
Copper
C.
Lead
D.
Water
Ans:
Water
Explanation :
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C which is higher than any other common substance. As a result, water plays a very important role in temperature regulation
[23] The device used for locating submerged objects under sea is –
A.
sonar
B.
radar
C.
laser
D.
maser
Ans:
sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
Heat capacity (usually denoted by a capital C, often with subscripts), or thermal capacity, is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount. In the International System of Units (SI), heat capacity is expressed in units of joule(s) (J) per Kelvin (K).
[12] Which of the following statements is true when we see 'rainbow'?
A.
We face sun and raindrops
B.
The Sun remains behind us and we face raindrops
C.
In light rainfall, we face Sun
D.
The sky remains clear and the sun is at lower position in the sky
Ans:
The Sun remains behind us and we face raindrops
Explanation :
We see rainbows because of the geometry of raindrops. When the sun shines from behind us into the rain, incident rays of light enter the drop and are refracted inwards. They are reflected from the back surface of the raindrop, and refracted again as they exit the raindrop and return to our eyes. A rainbow is an optical and meteorological phenomenon that is caused by reflection of light in water droplets in the Earth's atmosphere, resulting in a spectrum of light appearing in the sky.
[13] If the temperature of a place increases suddenly, the relative humidity –
A.
Increases
B.
Decreases
C.
Remains constant
D.
Fluctuates
Ans:
Decreases
Explanation :
Relative humidity is the ratio of the partial pressure of water vapor in an air-water mixture to the saturated vapor pressure of water at a prescribed temperature. The relative humidity of air depends not only on temperature but also on the pressure of the system of interest. If the system at State A is isobarically heated (heating with no change in system pressure) then the relative humidity of the system decreases because the saturated vapor pressure of water increases with increasing temperature.
[14] Pulsars are :
A.
stars moving towards the Earth
B.
stars moving away from Earth
C.
rapidly spinning stars
D.
high temperature stars
Ans:
rapidly spinning stars
Explanation :
Pulsars are celestial objects, thought to be rapidly spinning stars, that emits regular pulses of radio waves and other electromagnetic radiation at the rate of upto one thousand pulses per second.
[15] Tungsten is used for the manufacture of the filament of an electric bulb, because –
A.
It is a good conductor
B.
It is economical
C.
It is malleable
D.
It has a very high melting point
Ans:
It has a very high melting point
Explanation :
Tungsten is used because it has the highest melting point of all the metallic elements. It melts at 3410 degrees Celsius. When current passes through the filament it heats it up. When the filament reaches a certain temperature it starts to give off light, that's how we get a light bulb. The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo).
[16] What is the wavelength of visible spectrum?
A.
1300 A° -3000 A°
B.
3900 A° - 7600 A°
C.
7800 A° - 8000 A°
D.
8500 A° - 9800 A°
Ans:
3900 A° - 7600 A°
Explanation :
The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 750 nm in terms of angstrom it is in between 3900 - 7600 A°.
[17] The shape of our Milky Way galaxy is –
A.
circular
B.
elliptical
C.
spiral
D.
None of the above
Ans:
spiral
Explanation :
The Milky Way is a barred spiral galaxy 100,000-120,000 light-years in diameter containing 200-400 billion stars. It may contain at least as many planets, with an estimated 10 billion of those orbiting in the habitable zone of their parent stars. The Milky Way is the galaxy that contains our Solar System. This name derives from its appearance as a dim "milky" glowing band arching across the night sky, in which the naked eye cannot distinguish individual stars.
[18] The different colours of different stars are due to the variation of –
A.
temperature
B.
pressure
C.
density
D.
radiation from them
Ans:
temperature
Explanation :
Shortly after blackbody radiation was understood, it was noticed that the spectra of stars look extremely similar to blackbody radiation curves of various temperatures, ranging from a few thousand Kelvin to ~50,000 Kelvin. The obvious conclusion is that stars are similar to blackbodies, and that the colour variation of stars is a direct consequence of their surface temperatures.
[19] The splitting of different colours of light in a prism is :
A.
Reflection of light
B.
Dispersion light
C.
Diffraction light
D.
Refraction of light
Ans:
Dispersion light
Explanation :
The refractive index of many materials (such as glass) varies with the wavelength or colour of the light used, a phenomenon known as dispersion. This causes light of different colours to be refracted differently and to leave the prism at different angles, creating an effect similar to a rainbow. In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency, or alternatively when the group velocity depends on the frequency.
[20] A boat will submerge when it displaces water equal to its own:
A.
volume
B.
weight
C.
surface area
D.
density
Ans:
weight
Explanation :
A boat will float when the weight of the water it displaces equals the weight of the boat and anything will float if it is shaped to displace its own weight of water before it reaches the point where it will submerge. Floating of the boat works on the principle of buoyancy force which is an upward force exerted by a liquid, gas or other fluid, that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.
[21] Anemometer is used to measure –
A.
wind direction
B.
wind velocity
C.
pressure gradient
D.
wind speed and time
Ans:
wind velocity
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The first known description of an anemometer was given by Leon Battista Alberti around 1450.
[22] Which one of the following has the highest value of specific heat?
A.
Glass
B.
Copper
C.
Lead
D.
Water
Ans:
Water
Explanation :
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C which is higher than any other common substance. As a result, water plays a very important role in temperature regulation
[23] The device used for locating submerged objects under sea is –
A.
sonar
B.
radar
C.
laser
D.
maser
Ans:
sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
Relative humidity is the ratio of the partial pressure of water vapor in an air-water mixture to the saturated vapor pressure of water at a prescribed temperature. The relative humidity of air depends not only on temperature but also on the pressure of the system of interest. If the system at State A is isobarically heated (heating with no change in system pressure) then the relative humidity of the system decreases because the saturated vapor pressure of water increases with increasing temperature.
[14] Pulsars are :
A.
stars moving towards the Earth
B.
stars moving away from Earth
C.
rapidly spinning stars
D.
high temperature stars
Ans:
rapidly spinning stars
Explanation :
Pulsars are celestial objects, thought to be rapidly spinning stars, that emits regular pulses of radio waves and other electromagnetic radiation at the rate of upto one thousand pulses per second.
[15] Tungsten is used for the manufacture of the filament of an electric bulb, because –
A.
It is a good conductor
B.
It is economical
C.
It is malleable
D.
It has a very high melting point
Ans:
It has a very high melting point
Explanation :
Tungsten is used because it has the highest melting point of all the metallic elements. It melts at 3410 degrees Celsius. When current passes through the filament it heats it up. When the filament reaches a certain temperature it starts to give off light, that's how we get a light bulb. The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo).
[16] What is the wavelength of visible spectrum?
A.
1300 A° -3000 A°
B.
3900 A° - 7600 A°
C.
7800 A° - 8000 A°
D.
8500 A° - 9800 A°
Ans:
3900 A° - 7600 A°
Explanation :
The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 750 nm in terms of angstrom it is in between 3900 - 7600 A°.
[17] The shape of our Milky Way galaxy is –
A.
circular
B.
elliptical
C.
spiral
D.
None of the above
Ans:
spiral
Explanation :
The Milky Way is a barred spiral galaxy 100,000-120,000 light-years in diameter containing 200-400 billion stars. It may contain at least as many planets, with an estimated 10 billion of those orbiting in the habitable zone of their parent stars. The Milky Way is the galaxy that contains our Solar System. This name derives from its appearance as a dim "milky" glowing band arching across the night sky, in which the naked eye cannot distinguish individual stars.
[18] The different colours of different stars are due to the variation of –
A.
temperature
B.
pressure
C.
density
D.
radiation from them
Ans:
temperature
Explanation :
Shortly after blackbody radiation was understood, it was noticed that the spectra of stars look extremely similar to blackbody radiation curves of various temperatures, ranging from a few thousand Kelvin to ~50,000 Kelvin. The obvious conclusion is that stars are similar to blackbodies, and that the colour variation of stars is a direct consequence of their surface temperatures.
[19] The splitting of different colours of light in a prism is :
A.
Reflection of light
B.
Dispersion light
C.
Diffraction light
D.
Refraction of light
Ans:
Dispersion light
Explanation :
The refractive index of many materials (such as glass) varies with the wavelength or colour of the light used, a phenomenon known as dispersion. This causes light of different colours to be refracted differently and to leave the prism at different angles, creating an effect similar to a rainbow. In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency, or alternatively when the group velocity depends on the frequency.
[20] A boat will submerge when it displaces water equal to its own:
A.
volume
B.
weight
C.
surface area
D.
density
Ans:
weight
Explanation :
A boat will float when the weight of the water it displaces equals the weight of the boat and anything will float if it is shaped to displace its own weight of water before it reaches the point where it will submerge. Floating of the boat works on the principle of buoyancy force which is an upward force exerted by a liquid, gas or other fluid, that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.
[21] Anemometer is used to measure –
A.
wind direction
B.
wind velocity
C.
pressure gradient
D.
wind speed and time
Ans:
wind velocity
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The first known description of an anemometer was given by Leon Battista Alberti around 1450.
[22] Which one of the following has the highest value of specific heat?
A.
Glass
B.
Copper
C.
Lead
D.
Water
Ans:
Water
Explanation :
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C which is higher than any other common substance. As a result, water plays a very important role in temperature regulation
[23] The device used for locating submerged objects under sea is –
A.
sonar
B.
radar
C.
laser
D.
maser
Ans:
sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
Tungsten is used because it has the highest melting point of all the metallic elements. It melts at 3410 degrees Celsius. When current passes through the filament it heats it up. When the filament reaches a certain temperature it starts to give off light, that's how we get a light bulb. The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo).
[16] What is the wavelength of visible spectrum?
A.
1300 A° -3000 A°
B.
3900 A° - 7600 A°
C.
7800 A° - 8000 A°
D.
8500 A° - 9800 A°
Ans:
3900 A° - 7600 A°
Explanation :
The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 750 nm in terms of angstrom it is in between 3900 - 7600 A°.
[17] The shape of our Milky Way galaxy is –
A.
circular
B.
elliptical
C.
spiral
D.
None of the above
Ans:
spiral
Explanation :
The Milky Way is a barred spiral galaxy 100,000-120,000 light-years in diameter containing 200-400 billion stars. It may contain at least as many planets, with an estimated 10 billion of those orbiting in the habitable zone of their parent stars. The Milky Way is the galaxy that contains our Solar System. This name derives from its appearance as a dim "milky" glowing band arching across the night sky, in which the naked eye cannot distinguish individual stars.
[18] The different colours of different stars are due to the variation of –
A.
temperature
B.
pressure
C.
density
D.
radiation from them
Ans:
temperature
Explanation :
Shortly after blackbody radiation was understood, it was noticed that the spectra of stars look extremely similar to blackbody radiation curves of various temperatures, ranging from a few thousand Kelvin to ~50,000 Kelvin. The obvious conclusion is that stars are similar to blackbodies, and that the colour variation of stars is a direct consequence of their surface temperatures.
[19] The splitting of different colours of light in a prism is :
A.
Reflection of light
B.
Dispersion light
C.
Diffraction light
D.
Refraction of light
Ans:
Dispersion light
Explanation :
The refractive index of many materials (such as glass) varies with the wavelength or colour of the light used, a phenomenon known as dispersion. This causes light of different colours to be refracted differently and to leave the prism at different angles, creating an effect similar to a rainbow. In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency, or alternatively when the group velocity depends on the frequency.
[20] A boat will submerge when it displaces water equal to its own:
A.
volume
B.
weight
C.
surface area
D.
density
Ans:
weight
Explanation :
A boat will float when the weight of the water it displaces equals the weight of the boat and anything will float if it is shaped to displace its own weight of water before it reaches the point where it will submerge. Floating of the boat works on the principle of buoyancy force which is an upward force exerted by a liquid, gas or other fluid, that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.
[21] Anemometer is used to measure –
A.
wind direction
B.
wind velocity
C.
pressure gradient
D.
wind speed and time
Ans:
wind velocity
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The first known description of an anemometer was given by Leon Battista Alberti around 1450.
[22] Which one of the following has the highest value of specific heat?
A.
Glass
B.
Copper
C.
Lead
D.
Water
Ans:
Water
Explanation :
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C which is higher than any other common substance. As a result, water plays a very important role in temperature regulation
[23] The device used for locating submerged objects under sea is –
A.
sonar
B.
radar
C.
laser
D.
maser
Ans:
sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
The Milky Way is a barred spiral galaxy 100,000-120,000 light-years in diameter containing 200-400 billion stars. It may contain at least as many planets, with an estimated 10 billion of those orbiting in the habitable zone of their parent stars. The Milky Way is the galaxy that contains our Solar System. This name derives from its appearance as a dim "milky" glowing band arching across the night sky, in which the naked eye cannot distinguish individual stars.
[18] The different colours of different stars are due to the variation of –
A.
temperature
B.
pressure
C.
density
D.
radiation from them
Ans:
temperature
Explanation :
Shortly after blackbody radiation was understood, it was noticed that the spectra of stars look extremely similar to blackbody radiation curves of various temperatures, ranging from a few thousand Kelvin to ~50,000 Kelvin. The obvious conclusion is that stars are similar to blackbodies, and that the colour variation of stars is a direct consequence of their surface temperatures.
[19] The splitting of different colours of light in a prism is :
A.
Reflection of light
B.
Dispersion light
C.
Diffraction light
D.
Refraction of light
Ans:
Dispersion light
Explanation :
The refractive index of many materials (such as glass) varies with the wavelength or colour of the light used, a phenomenon known as dispersion. This causes light of different colours to be refracted differently and to leave the prism at different angles, creating an effect similar to a rainbow. In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency, or alternatively when the group velocity depends on the frequency.
[20] A boat will submerge when it displaces water equal to its own:
A.
volume
B.
weight
C.
surface area
D.
density
Ans:
weight
Explanation :
A boat will float when the weight of the water it displaces equals the weight of the boat and anything will float if it is shaped to displace its own weight of water before it reaches the point where it will submerge. Floating of the boat works on the principle of buoyancy force which is an upward force exerted by a liquid, gas or other fluid, that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.
[21] Anemometer is used to measure –
A.
wind direction
B.
wind velocity
C.
pressure gradient
D.
wind speed and time
Ans:
wind velocity
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The first known description of an anemometer was given by Leon Battista Alberti around 1450.
[22] Which one of the following has the highest value of specific heat?
A.
Glass
B.
Copper
C.
Lead
D.
Water
Ans:
Water
Explanation :
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C which is higher than any other common substance. As a result, water plays a very important role in temperature regulation
[23] The device used for locating submerged objects under sea is –
A.
sonar
B.
radar
C.
laser
D.
maser
Ans:
sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
The refractive index of many materials (such as glass) varies with the wavelength or colour of the light used, a phenomenon known as dispersion. This causes light of different colours to be refracted differently and to leave the prism at different angles, creating an effect similar to a rainbow. In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency, or alternatively when the group velocity depends on the frequency.
[20] A boat will submerge when it displaces water equal to its own:
A.
volume
B.
weight
C.
surface area
D.
density
Ans:
weight
Explanation :
A boat will float when the weight of the water it displaces equals the weight of the boat and anything will float if it is shaped to displace its own weight of water before it reaches the point where it will submerge. Floating of the boat works on the principle of buoyancy force which is an upward force exerted by a liquid, gas or other fluid, that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.
[21] Anemometer is used to measure –
A.
wind direction
B.
wind velocity
C.
pressure gradient
D.
wind speed and time
Ans:
wind velocity
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The first known description of an anemometer was given by Leon Battista Alberti around 1450.
[22] Which one of the following has the highest value of specific heat?
A.
Glass
B.
Copper
C.
Lead
D.
Water
Ans:
Water
Explanation :
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C which is higher than any other common substance. As a result, water plays a very important role in temperature regulation
[23] The device used for locating submerged objects under sea is –
A.
sonar
B.
radar
C.
laser
D.
maser
Ans:
sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The first known description of an anemometer was given by Leon Battista Alberti around 1450.
[22] Which one of the following has the highest value of specific heat?
A.
Glass
B.
Copper
C.
Lead
D.
Water
Ans:
Water
Explanation :
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C which is higher than any other common substance. As a result, water plays a very important role in temperature regulation
[23] The device used for locating submerged objects under sea is –
A.
sonar
B.
radar
C.
laser
D.
maser
Ans:
sonar
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water.
[24] The working principle of a 'Washing machine' is :
A.
centrifugation
B.
dialysis
C.
reverse osmosis
D.
diffusion
Ans:
centrifugation
Explanation :
The principle behind the spinning dry of the clothes in a washing machine is centrifugal force. The fast spinning around of the clothes in the drum creates a large centrifical force from center to the edge of the drum, and the wet clothes are flung outwards to the drum edge and the water escapes through the drum holes.
[25] Instrument used to measure the force and velocity of the wind is –
A.
Ammeter
B.
Anemometer
C.
Altimeter
D.
Audiometer
Ans:
Altimeter
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.
Explanation :
An anemometer is a device for measuring wind speed, and is a common weather station instrument. The term is derived from the Greek word anemos, meaning wind, and is used to describe any airspeed measurement instrument used in meteorology or aerodynamics. Anemometers can be divided into two classes: those that measure the wind's speed, and those that measure the wind's pressure; but as there is a close connection between the pressure and the speed, an anemometer designed for one will give information about both.