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
Correct Answer :
C. bad conductor of electricity
Related Questions
The method used to separate aluminium from a alumina is
electroplating
electrotyping
electrolysis
distillation
The hydraulic jack to lift heavy vehicles in automobile service stations is one of the applications of
Pascal's law
Principle of Archimedes
Boyle's law
Hooke's law
Cosmic rays contain
protons and electrons
alpha particles
gamma rays
All the above
A bullet is fired at a certain angle with the horizontal. Its path will be
elliptical
a straight line
a parabola
a vertical line
The radiator in a car serves to
cool the engine
heat up the engine
start the car
moderate the speed
We see the sun before it actually rises on the horizon. This is due to
refraction
reflection
total internal reflection
parallax
When an incident beam of light strikes the surface of a glass slab normally, the refracted beam
goes straight through without bending
gets deviated away from the normal
gets bent towards the normal
gets reflected
In a refrigerator, the refrigerant is
Nitrogen
Oxygen
Chlorine
Freon
The planet that moves fastest around the sun is
Mars
Venus
Earth
Mercury
An electric fan converts
electrical energy into heat energy
electrical energy into mechanical energy
mechanical energy into electrical energy
mechanical energy into heat energy
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
In the visible spectrum which colour has the shortest wavelength?
Red
Blue
Yellow
Violet
The coil of an electric heater is made of
Platinum
Tungsten
Nichrome
Copper
Mercury does not stick to glass because
cohesive forces between the mercury molecules are greater than adhesive forces between mercury and glass molecules
the adhesive forces between mercury and glass molecules are greater than the cohesive forces
both the cohesive and adhesive forces are equal
None of the above
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
When we tighten the string of a sitar or tanpura its pitch
remains the same
increases
decreases
None of the above
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
The attraction of unlike molecules at the common surface is known as
adhesion
cohesion
surface tension
capillarity
A stationary elevated object has
kinetic energy
potential energy
momentum
both potential and kinetic energy
One finds it more difficult to walk on ice than on a concrete road because
there is more friction on ice than on concrete surface
ice is soft and spongy while concrete is hard
the friction between ice and the feet is less than that between the concrete and the feet
None of them
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
Gamma radiations are used for
sterilising food stuff
controlling pests
cancer therapy
All of these
In a river, the currents are fastest where the river la
wide and shallow
narrow and shallow
wide and deep
narrow and deep
The electroplating of a metallic article
protects the article from atmospheric corrosion
gives it a more attractive appearance
Both (a) and (b) above
None of the above
The characteristics of a musical note are
loudness
pitch
quality or timbre
All the above
The device used to record the sound is
a microphone
a headphone
a phonograph
an amplifier
Which of the following rays has the highest penetrative power?
�± -rays
�² -rays
�³ -rays
X-rays
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 presence of impurities
lowers the melting point of ice
raises the melting point of ice
has no effect on the melting point of ice
may lower or raise the melting point depending upon the type of impurities
The electron has a mass equal to
1.9 x 10-13 kg
9.1 x 10-31 kg
1 x 10-15 kg
1.6 x 10-19 kg