Where does the centre of gravity of a rubber ring lie?
on the outer surface
in the inner surface
at the centre of the ring
None of the above
Correct Answer :
C. at the centre of the ring
Related Questions
If a body is taken from the earth to the moon
both its mass and weight will be different
its mass will be different but the weight will remain the same
its mass and weight will both remain unchanged
its mass will remain the same but weight will be different
An electric fan converts
electrical energy into heat energy
electrical energy into mechanical energy
mechanical energy into electrical energy
mechanical energy into heat energy
In a dynamo
mechanical energy is converted to light energy
mechanical energy is converted to heat energy
mechanical energy is converted to electrical energy
electrical energy is converted to mechanical energy
The largest planet in the solar system is
Neptune
Uranus
Jupiter
Saturn
In a microphone
sound energy is converted into electrical energy
electrical energy is converted into sound energy
sound energy is converted into mechanical energy
mechanical energy is converted into sound energy
A hydrogen bomb is based on
nuclear fusion
nuclear fission
Both (a) and (b) above
Neither (a) nor (b)
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
The star nearest to the sun is
Proxima Centauri
Sirius
Aldebaran
Vega
To concentrate light on the defective teeth, the dentists use
convex mirrors
concave mirrors
convex lens
concave lens
It is difficult to bon potatoes at the top or a mountain because
the water available is hard
it is colder than at sea level
the potatoes become hard
the boiling point of water is lower at that height on account of low atmospheric pressure
Two tumblers stuck together can be separated by
pouring ice cold water into the inner tumbler
pouring ice cold water on the outer tumbler
pouring hot water into the inner tumbler
dipping both the tumblers in hot water
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
The escape velocity of a satellite projected from the surface of the earth is independent of
the mass of earth
the mass of the satellite
the radius of the earth
gravitation of the earth
The property of a fluid by which it resists relative motion within itself is known as
cohesive force
surface tension
diffusion
viscosity
The earth's nearest neighbour in space is
the Sun
the Moon
the Venus
the Mars
Why is nuclear fusion also known as thermonuclear reaction?
Fusion converts nuclear energy into heat
Fusion demands conditions of extremely high temperature to produce it
Fusion produces large amount of heat
Fusion reactions takes place in the sun
When the earth reaches its perihelion
it is nearest to the moon
it is nearest to the sun
it is nearest to Pluto
it is farthest from the sun
Which of the following revolves round the nucleus in an atom?
protons
electrons
neutrons
positrons
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
At what temperature do the Fahrenheit and Kelvin scales give the same reading?
212°
32°
-40°
0°
Which of the following apparatus is used in the electrolysis of water?
Voltmeter
Voltameter
Ammeter
Potentiometer
The method used to separate aluminium from a alumina is
electroplating
electrotyping
electrolysis
distillation
A tube light works on the principle of
chemical, heating and magnetic effects of electricity
discharge of electricity through gases
the action of ultraviolet radiation on certain fluorescent materials
Both (b) and (c) above
A balloon ruled with hydrogen will
continue going upwards uninterrupted
reach a particular height and remain floating
burst after reaching some height
reach a particular height and start coming down
When the velocity of a body is halved
its momentum is halved
its kinetic energy is halved
its acceleration is halved
its potential energy is halved
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 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
The direction of heat flow between two objects depends on
their heat contents
their masses
their temperatures
whether they are in solid, liquid or gaseous state
A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will
increase
decrease
remain unaffected
have its shape changed
Raindrops assume a spherical shape because or
adhesion
surface tension
gravitational force
atmospheric pressure from all sides