Choose the correct answer
Microphone converts sound energy into electrical energy.
Electric fan converts electrical energy into mechanical energy.
Battery converts chemical energy into electrical energy.
All the above
Correct Answer :
D. All the above
Related Questions
Choose the scalar quantity from the following physical quantities
force
velocity
acceleration
speed
When an electric bulb breaks, there la an explosive sound. That is due to
the chemical reaction between the gases inside the bulb
the compressed gases inside rushing out suddenly
the air outside rushing in to fill the vacuum inside the bulb
None of the above
At temperature near OK, (zero kelvin) metals such as lead and tin become
insulators
semiconductors
superconductors
condenser
The maximum displacement of the particle in a mechanical wave motion is known as
amplitude
vibration
frequency
phase
Cosmic rays are
powerful X-rays falling on the earth from space
ultraviolet rays from the sun
gamma rays from radioactive minerals
very energetic radiation falling upon the earth from outer space consisting chiefly of charged particles
The maximum range of most TV signals is from 121 to 240 km only because
the curvature of earth limits the range of reception
the signals are weak
the signals are absorbed by air
the antennae are not powerful enough
Less dew is formed on cloudy nights because
there is no moisture in the atmosphere
clouds absorb the falling dew
objects emit radiant energy very fast on such nights
objects lose less radiant energy
A boy sitting in a train moving with a uniform velocity drops a coin outside. A man standing outside the train will find the trajectory of the coin to be
a parabola
a horizontal straight line
a vertical straight line
a circle
Mica is used in an electric iron because it is a
good conductor of heat
good conductor of electricity
bad conductor of electricity
Both (a) and (b) above
An integrated circuit is more advantageous than a conventional circuit because
they make the electric equipment more reliable and easier for servicing
a faulty part of a conventional circuit may be difficult to locate and repair
if a part of the integrated circuit fails the entire circuit is simply replaced
All the above
Which of the following wires of same dimensions offers least resistance to the ,flow of current?
copper
aluminium
silver
nichrome
Rain drops acquire spherical shape due to
viscosity
surface tension
friction
elasticity
Alpha particles are
electromagnetic radiations
helium nuclei
negatively charged particles
neutral particles
The best estimates of the age of the earth comes from the studies of
angle of inclination of the earth
changes in radio-active minerals in it
period taken by Sun's light to reach the earth
artificial satellites revolving round the earth
When a ship floats on water, the weight or water displaced is
an indeterminate quantity
equal to the weight of the ship
greater than the weight of the ship
less than the weight of the ship
The line on earth's surface passing through the places having zero dip is called the magnetic equator. This passes through
Thumba
Delhi
Mumbai
Sriharikota
A stone floor feels cold to the bare feet but a carpet on the same floor feels warm. This is because
the floor and carpet are at different temperatures
the stone conveys the heat away from the feet more rapidly than the carpet
the carpet is a better conductor of heat than the stone
the human body maintains a constant temperature
When a bullet is fired from a gun
the gun moves forward
the gun jumps up
the gun does not move
the gun recoils with the same momentum as the bullet
A ruse wire is characterised by
high resistance and high melting point
high resistance and low melting point
low resistance and high melting point
low resistance and low melting point
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
To produce beats it is necessary to have two waves
travelling in opposite direction
of slightly different frequencies
of equal wavelength
of equal amplitude
The power of a lens is
equal to its focal length
equal to its radius of curvature
equal to the reciprocal of its focal length (in metres)
equal to twice its focal length
Lightning is produced when
similar charges of electricity rush towards each other and then get repelled
clouds strike against impurities in air and the friction burns up these impurities
strong opposite charges in different clouds break down the resistance offered by the intervening air
water vapour produces electricity in the clouds
When a light ray is reflected repeatedly by a set of parallel plane mirrors, the intensity of light ray diminishes alter a few reflections. This is because of
poor reflection from the mirrors
scattering of light from the mirrors
absorption of some light by the mirrors
absorption of light by the atmosphere
In a refrigerator cooling is produced by
the ice that deposits on the freezer
the evaporation of a volatile liquid
None of the above
Both (a) and (b)
A hydraulic brake in an automobile uses
a fluid to transmit the braking force
the force applied by the driver
hydrogen gas and not any liquid
a vacuum brake
Raindrops assume a spherical shape because or
adhesion
surface tension
gravitational force
atmospheric pressure from all sides
A convex mirror always produces
an erect, virtual image of diminished size
an erect, real image of diminished size
an erect, real image of double size
a virtual image of double size
Which of the following pairs is not correct?
Television - Baird
Transistor ~ Shockley
Thermometer - Celsius
Barometer Torricelli
Rays from the headlight of a motor car are rendered parallel by suitably using
a convex mirror behind it
a concave lens behind it
a concave mirror in front of it
a concave mirror behind it