Pieces of camphor placed on water move about rapidly. This is because of
diffusion
viscosity
surface tension
capillarity
Correct Answer :
C. surface tension
Related Questions
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
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
Which is the densest planet of the solar system?
Sun
Jupiter
Mercury
Earth
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 ice melts, Its volume
decreases
increases
remains the same until all the ice has melted and then increases
remains the same
When we tighten the string of a sitar or tanpura its pitch
remains the same
increases
decreases
None of the above
Sound waves in air are
transverse
longitudinal
transverse and longitudinal
neither transverse nor longitudinal
Rain drops acquire spherical shape due to
viscosity
surface tension
friction
elasticity
The mode of travel of heat energy from the sun across the empty space beyond the earth's atmosphere is known as
conduction
convection
radiation
absorption
Expansion of a rod when heated
is proportional to its original length
is proportional to the increase of temperature
is inversely proportional to its original length
Both (a) and (b) above
The mixing up of two gases as a result of random motion of molecules is called
diffusion
effusion
vaporisation
sublimation
Body A is kept in contact with body B. Heat will flow from A to B if
the heat content of A is greater than that of B
the temperature of A is greater than that of B
the specific heat of A is greater than that of B
the specific heat of B is greater than that of A
A series of east moving still pictures can be made to appear as a moving picture because the eye
can focus very rapidly as pictures change
is quicker than the brain
can see two images separated only if the interval' between seeing them is more than' one-tenth of a second
can shut out some of the light
In a hydraulic pressure
force on each square centimetre of the small piston is less than the force on each square centimetre of the large piston
the distance the small piston moves is equal to the distance the large piston moves
applied pressure is equally transmitted throughout the liquid in all directions
force acting on small piston is equal to the force acting on large piston
If an empty cylinder Is half ruled with a liquid, Its centre of gravity is
shifted upwards
shifted downwards
shifted neither upward nor downward
shifted upward or downward depending on the density of the liquid
Drinks kept in a vacuum flask remain hot or cold as the case may be for a long time because
both walls are silvered on the vacuum side
there is vacuum between the double walls
the cork is a poor conductor of heat
of all the above
For an electron orbiting in a hydrogen atom, the necessary centripetal force keeping it in orbit is provided by
the electrical attraction between the negatively charged electron and the positively charged porton
the high speed of the electron
the low speed of the electron
gravity
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
An electric fan converts
electrical energy into heat energy
electrical energy into mechanical energy
mechanical energy into electrical energy
mechanical energy into heat energy
A lightning conductor installed in a building
does not allow the lightning to fall on the building at all
drives away the charged clouds
forces the lightning to fall on other buildings near that building
conducts the electric charges to the ground when lightning strikes the building
A pair of stars that revolve round each other is
a neutron star
a binary star
a dwarf star
a polar star
Velocity of sound in high altitudes is low because at such a height
the temperature is low
there is no air
the pressure is low
All the above
A pressure gauge for fluids is called
a hydrometer
a manometer
a lactometer
an anemometer
The Cact that the compass needle does not point true north was observed first by
Sir Isaac Newton
Columbus
Archimedes
Thomas Alva Edison
In a freezer ice cubes will be formed more quickly in trays made of
rubber
plastic
aluminium
wood
The resistance of a wire depends on
the material of the wire
the length of the wire
the cross section of the wire
All the above
When a whistling engine approaches a person standing on the platform, the frequency or the note
appears to increase
appears to decrease
does not change at all
first increases then decreases
The unit of power in SI is
Joule
Newton
Joule/Sec
Erg/Sec
When a body is partly or wholly immersed in a liquid the apparent loss of weight is equal to the weight of the liquid displaced by the submerged portion. This is known as
Pascal's law
Bernoulli's law
Archimedes' law
Boyle's law
The unit of heat energy is
watt
degree
joule
erg