Photo-electric cells convert
electrical energy into light energy
light energy into electrical energy
light energy into heat energy
electrical energy into heat energy
Correct Answer :
B. light energy into electrical energy
Related Questions
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
The unit of power in SI is
Joule
Newton
Joule/Sec
Erg/Sec
In an oil lamp, holes are provided below the chimney so that
necessary oxygen for burning of oil may be provided
the convection current of air may be maintained to keep the lamp burning
the brightness of the lamp may be increased
All the above
The brightest star visible to the naked eye is
Sirius
Vega
Rigel
Proxima Centauri
Solids have definite shapes. This is because
the forces of cohesion of the molecules within are very much less in them
the forces of cohesion are very large
the forces of adhesion are large
the forces of adhesion are less
A small bubble of air deep down in a lake rises up to the top of the lake. The volume of the bubble on coming up will
increase
decrease
will not change
first increase and then decrease
The attraction between similar molecules is called
inertia
adhesion
cohesion
friction
The velocity of sound in a medium is
directly proportional to its pressure
inversely proportional to the square root of its pressure
directly proportional to the square root of its pressure
independent of its pressure
To concentrate light on the defective teeth, the dentists use
convex mirrors
concave mirrors
convex lens
concave lens
The rocket engine is motivated by jet propulsion which uses the famous
Kepler's Laws
Newtonian Third Law of Motion
Bernoulli's Principle
Law of Relativity
Which physical quantity is measured in watts
power
kinetic energy
momentum
impulse
A piece of cork la embedded inside an ice block which floats in water. What will happen to the level of water when all ice melts?
It will go down
It will come up
It will remain at the same level
First it will go down and it will come up
A man stands in a lift which accelerates upwards. The resultant reaction force on the floor of the lift is
greater than the weight of the man
less than the weight of the man
same as the weight of the man
zero
A light year means
a unit of time
a unit of length
a year of no consequence
illumination throughout the year
Metals are good conductors of heat because
they contain free electrons
their atoms are relatively far apart
their atoms collide frequently
they have reflecting surfaces
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
When water is cooled from 4�C to 2�C its density
increases
decreases
remains the same
first increases then decreases
The device that is used to measure the electromotive force of a cell is
an ammeter
a rheostat
a voltmeter
a voltameter
The stem of a vibrating tuning fork is pressed against a sound box. Then
the loudness of the sound increases
the loudness remains the same
the loudness decreases
the sound suddenly stops
Antiparticle of electron is
proton
antiproton
positron
neutron
The phenomenon of spontaneous disintegration of certain heavy nuclei is termed
radioactivity
fission
fusion
implosion
The method used to separate aluminium from a alumina is
electroplating
electrotyping
electrolysis
distillation
The unit of power in SI is
Joule
Newton
Joule/Sec
Erg/Sec
In an electrical circuit, a fuse is connected
in the live wire
in the neutral wire
in the earth wire
anywhere
The largest planet in the solar system is
Neptune
Uranus
Jupiter
Saturn
The theory that the earth constituted the centre of the universe around which the sun and the planets revolved was propounded by
Copernicus
Ptolemy
Newton
Kepler
The scientist who first sent electromagnetic waves to distant places was
James Clerk Maxwell
Heinrich Hertz
Thomas Alva Edison
Baird
The aneroid barometer uses
mercury
distilled water
alcohol
does not use any liquid
Hot water is poured simultaneously in four metallic tumblers painted outside with different paints. After some time the water will be found to have cooled most in the tumbler painted.
rough white
rough black
shining white
shining black
An ohm is a unit of
potential difference
resistance
current
All the above