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
Correct Answer :
D. current may pass to the earth in case of a short circuit without doing any harm to the person
Related Questions
Nuclear fission process means
absorption of a neutron by a nucleus
breakup of the nucleus of a heavy atom into two nearly equal halves emitting two or three neutrons and releasing large amounts of nuclear energy in the process
the scattering of neutrons
formation of heavier nucleus
X-rays are
deflected by electric field
deflected by magnetic field
slightly deflected by electric field and magnetic field
not deflected by electric and magnetic fields
Antiparticle of electron is
proton
antiproton
positron
neutron
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
The period of oscillation of a simple pendulum depends upon
the mass of its bob
the material of the bob
the amplitude of vibration
acceleration due to the gravity at the site of experiment
To get 5 images of a single object one should have two plane mirrors inclined at an angle of
72°
60°
36°
90°
Red Light is used as a dancer signal because
it is pleasing to the eye
it has a traditional colour
it is easily distinguishable
it is most sensitive to the human eye
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)
Water kept in an earthen pot is less cool on rainy days than in summer because during the rainy days
the pores in the pot are closed
rain water stops oozing out from the pores
the water that oozes out does not evaporate quickly because of the large percentage of moisture in the air
surface of the pot becomes damp
The colour of the light which travels through glass with minimum speed is
red
violet
green
yellow
Nuclear fusion is a process in which
the atoms and molecules lose their identity
nucleus is split into fragments
the nuclear reaction between two light atomic nuclei results in the formation of a heavier nucleus with release of a large quantity of nuclear energy in the process
absorption of neutron by a nucleus
If a bar magnet is broken into two pieces
both pieces will lose their magnetism
one piece will have North Pole on both ends and the other South Pole on its both ends
each will remain a magnet with North Pole at one end and South Pole at the other
the longer piece will behave as a bar magnet while the smaller will have no magnetism at all
When a body Is taken to the poles from the equator, Its weight becomes
greater
less
the same
None of these
A device used to measure heights above sea level is known as
altimeter
anemometer
dilatometer
potentiometer
We see the sun before it actually rises on the horizon. This is due to
refraction
reflection
total internal reflection
parallax
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
One can be recognised by his voice alone due to the factor of
quality
amplitude
pitch
loudness
Alpha particles are
electromagnetic radiations
helium nuclei
negatively charged particles
neutral particles
The Solar System lies near the edge of a galaxy known as
The Milky Way
Radio Galaxy
Andromeda Nebula
Magellanic Clouds
The minimum velocity required by a satellite to escape earth's gravitational pull is
18 km/s
11.2 km /s
21 km/s
35 km/s
A boy is swinging a ball attached to a string in a horizontal circle. If the string snaps
the ball will travel towards the centre of the circle and fall down
it will continue to travel along a tangent to the circle at the point the ball was at the time of snapping and finally fall down
it will fall down at the same place where the string breaks
None of these
The base of an electric iron is brightly polished mainly
to make it smooth and frictionless
to make it rust - proof
to reduce heat loss by radiation
to make it more durable
A hydrogen bomb is based on
nuclear fusion
nuclear fission
Both (a) and (b) above
Neither (a) nor (b)
A heavenly body similar in nature to the sun intensely hot glowing mass that produces its energy by thermonuclear reactions is
a planet
a meteor
a star
a comet
Which of the following pairs is not correct?
Television - Baird
Transistor ~ Shockley
Thermometer - Celsius
Barometer Torricelli
Sun spots are
the mountains found on the surface of the Sun
the dark patches on the sun having less temperature than the normal sun's surface
ionized gas found near the solar surface
the magnetic storms on the surface of the Sun
The characteristics of a musical note are
loudness
pitch
quality or timbre
All the above
How is it that Pluto is not always the farthest planet of the solar system?
Each planet becomes the farthest planet in its turn. Now it is the turn of Piuto
The Sun is now in the zodiac in which it is nearest to outer planets
The eccentricity of Piuto's orbit being substantial, this orbit cuts the orbit of Neptune
Piuto belongs to other solar system
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
Light from the sun reaches the earth in
2 minutes
4 minutes
12 minutes
8 minutes