When the velocity of a body is halved
its momentum is halved
its kinetic energy is halved
its acceleration is halved
its potential energy is halved
Correct Answer :
A. its momentum is halved
Related Questions
When the earth reaches its perihelion
it is nearest to the moon
it is nearest to the sun
it is nearest to Pluto
it is farthest from the sun
A radio set that uses valves does not start operating immediately when it is switched on whereas a set containing only tranaistors operates immediately. The reason for this is that
the valve filaments have low resistance
valve-radio sets work at a higher voltage
transistor set has a low resistance
filaments of the valves cake time to beat up and function
The method used to separate aluminium from a alumina is
electroplating
electrotyping
electrolysis
distillation
The difference between planets and stars is
planets do not have light of their own whereas stars shine by their own light
planets do not twinkle like stars
planets are much smaller than stars
All the above
Of the following which has got the highest frequency?
ultraviolet rays
gamma rays
radio waves
infrared waves
Photocells are used
in burglar alarms
in automotive devices for light switches
television cameras
All the above
Which of the following pairs is not correct?
Television - Baird
Transistor ~ Shockley
Thermometer - Celsius
Barometer Torricelli
Which of the following pairs is not correct?
Television - Baird
Transistor ~ Shockley
Thermometer - Celsius
Barometer Torricelli
The largest reserve of radioactive element which can be used in a nuclear reactor has been found in India, The name of the element is
Thorium
Uranium
Plutonium
Radium
Diamond shines because of its
purity
hardness
high density
high refractive index and low critical angle
A spherical mirror is
a reflecting elliptical portion
a reflecting spherical surface
a parabolic reflecting surface
a flat reflecting surface
When two similar sources vibrate with slightly different frequencies, a regular rise and fall occurs in the loudness of tone. This phenomenon Is known as
doppler effect
beats
resonance
echo
The difference between planets and stars is
planets do not have light of their own whereas stars shine by their own light
planets do not twinkle like stars
planets are much smaller than stars
All the above
The spectrum of white light can be studied by
a microscope
a telescope
a stereoscope
a spectroscope
Changing of one element into another element is known as
transmutation
fission
fusion
radioactivity
When white light passes through a glass prism we get a spectrum on the other side of the prism. In the emergent beam the ray which is deviated least is
the violet ray
the red ray
the green ray
the blue ray
In very cold countries alcohol is used as a thermometric liquid because
alcohol is a poor conductor of heat
alcohol can be coloured for its level to be seen easily
its freezing point is very low
it will not stick to the glass tube
A man Jumping out of a moving train is thrown
forward
backward
sideways
None of the above
The asteroids belt lies between the orbits of
Earth and Mars
Venus and Earth
Mars and Jupiter
Moon and Mars
We always see only one side of the moon because
the sun comes in between the earth and moon
the moon is stationary
the time taken by the moon to rotate on its axis is the same as the time taken by it to revolve round the earth
moon revolves round the sun
The overhead wires supported by high towers in the grid system carry
alternating current of very high frequency
alternating current of very high voltage
a very large direct current
a high voltage direct current
If an empty cylinder Is half ruled with a liquid, Its centre of gravity is
shifted upwards
shifted downwards
shifted neither upward nor downward
shifted upward or downward depending on the density of the liquid
In experiments on static electricity the standard method for obtaining small amounts of positive electricity is to rub
a glass rod with flannel
an abonite rod with flannel
a glass rod with silk
Any of the above
One can be recognised by his voice alone due to the factor of
quality
amplitude
pitch
loudness
A proton is
a quantum of light energy
a quantum of matter
a positively charged atomic particle
another name for positron
In the electrical circuit of a house the fuse acts as
a thermopile
a load
a step down device
a safety device
Meteors
look like falling stars
are really pieces of rock or metal
burn up as they shoot through the air
All the above
Why is nuclear fusion also known as thermonuclear reaction?
Fusion converts nuclear energy into heat
Fusion demands conditions of extremely high temperature to produce it
Fusion produces large amount of heat
Fusion reactions takes place in the sun
The planet that spins Caster than any other planet is
Saturn
Jupiter
Earth
Mercury
The phenomenon of spontaneous disintegration of certain heavy nuclei is termed
radioactivity
fission
fusion
implosion