A body has fallen from a height. Just before touching the pound it has
lost all its potential energy and gained an equivalent amount of kinetic energy
gained potential energy and lost kinetic energy
gained kinetic energy as well as potential energy
lost kinetic energy as well as potential energy
Correct Answer :
A. lost all its potential energy and gained an equivalent amount of kinetic energy
Related Questions
The function of a moderator in a nuclear reactor is
to absorb unwanted neutrons
to slow down the fast neutrons to secure more effective hits on other nuclei
to decrease the number of fissile nuclei
to increase the number of fissile nuclei
The body of an electrical appliance is earthed in order that
electricity may not leak
there may be smooth flow of electricity
a short circuit may be prevented
current may pass to the earth in case of a short circuit without doing any harm to the person
For an electron orbiting in a hydrogen atom, the necessary centripetal force keeping it in orbit is provided by
the electrical attraction between the negatively charged electron and the positively charged porton
the high speed of the electron
the low speed of the electron
gravity
At what temperature do the Fahrenheit and Kelvin scales give the same reading?
212°
32°
-40°
0°
Galaxies emit
radio waves and X-rays
ultraviolet light waves
visible light waves
All the above
The temperature of a large bucket-full of hot water (a few degrees below boiling point) is lower than a beaker full of boiling water. But
the hot water contains a much larger quantity of internal energy than the boiling water
the boiling water contains more quantity of internal energy than the warm water
both of them have got the same amount of internal energy.
nothing can be said definitely with the data given
A person cups his hand around the mouth when shouting. Why?
Sound energy from his mouth is then directed in one direction
The cupped hand acts as a cardboard tube of short length
The pitch of sound increases
Both (a) and (b)
If you want a sound proof room, the walls should be
able to refract the sound
good absorbers of sound
good reflectors of sound
All the above
To get 5 images of a single object one should have two plane mirrors inclined at an angle of
72°
60°
36°
90°
Pyrometers are instruments used
for measuring the velocity of wind
in the manufacture of fireworks
in finding the coefficient of apparent expansion of a liquid
for measuring high temperatures
In the ramous equation of Einstein E = mc2 , 'c' denotes.
velocity of sound
velocity of light
a constant factor
wavelength of light
The image of an object formed in a plane mirror
is real
is virtual
can be obtained on a screen
is slightly bigger than the object
The body of an electrical appliance is earthed in order that
electricity may not leak
there may be smooth flow of electricity
a short circuit may be prevented
current may pass to the earth in case of a short circuit without doing any harm to the person
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
The SI unit of electric current is
the ampere
the volt
the ohm
the coulomb
A man stands on the pan of a balance holding a fish in his right hand and bucket of water in his left hand. If he transfers the fish into the bucket, the total weight on the pan
increases
decreases
remains the same
first increases and then decreases
In hot climatic conditions, the buildings are painted white because
white paint is economical
it does not fade off
it does not crack with higher temperature
white coating is a bad conductor of heat and reflects heat rays that fall on it, thus keeping the inside cool
Echoes are produced by
the reflection of sound waves
the refraction of sound waves
the interference of sound waves
reverberation of sound waves
On the Kelvin scale, the melting point of ice is
0 K
273 K
373 K
100 K
The maximum displacement of the particle in a mechanical wave motion is known as
amplitude
vibration
frequency
phase
The image of an object formed on the retina of the eye is
virtual and upright
virtual and inverted
real and inverted
real and upright
Increase in pressure
has no effect on the boiling point of a liquid
raises the boiling point of a liquid
lowers the boiling point of a liquid
increases the volume of a liquid
The atmosphere gets heated up mainly by
direct sun's rays
radiation from earth's surface
radiogenic heat (resulting from radioactive decay)
cosmic rays coming from space
Sound waves in air are
transverse
longitudinal
transverse and longitudinal
neither transverse nor longitudinal
The device that is used to measure the electromotive force of a cell is
an ammeter
a rheostat
a voltmeter
a voltameter
Alternating Current (AC) is more advantageous than direct current because
it can be transmitted easily and efficiently
Alternating Current (AC) loses the least amount of energy when transmitted at high voltages
Alternating Current (AC) voltage can be easily increased or decreased
all the above
In a concert hall reverberation is controlled by
reduction of seating capacity in the hall
increase of sound intensity in the hall
lining the walls, with leather panels put on over a layer of sound absorbent glass fibre
by opening the doors and windows of concert hall
When a body Is taken to the poles from the equator, Its weight becomes
greater
less
the same
None of these
The ballistic missile, Agni 11, tested by India has a maximum range of
1000 km
1500 km
2000 km
500 km
Air pressure is usually highest when the air is
warm and moist
cool and dry
warm and dry
cool and moist