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
The number of electrons in the outer orbits of a nucleus gives
the mass number
atomic number
atomic weight
absolute number
The speed of light is minimum while passing through
air
glass
vacuum
water
Which part of the eye photographic camera?
Lens
Iris
Retina
Eyelid
A light year means
a unit of time
a unit of length
a year of no consequence
illumination throughout the year
The radiator in a car serves to
cool the engine
heat up the engine
start the car
moderate the speed
If a band is played on the moon the sound will
reverberate
be heard by us faintly
be heard upto 10 km from it
not be heard at any distance at all from it
In very cold countries alcohol is used as a thermometric liquid because
alcohol is a poor conductor of heat
alcohol can be coloured for its level to be seen easily
its freezing point is very low
it will not stick to the glass tube
The ozone layer absorbs
Cosmic rays
Infrared rays
All radiations of light
Ultra violet rays coming from the sun
Out of the following which element has the longest half-life period?
Radium
Radon
Uranium-238
Plutonium
Heat transfer
cools the body that transfers it
heats the body that absorbs the heat
may change the physical state of the substance
All the above
A car parked in the sun with its windows closed gets terribly hot inside. This is due to
the heat emitted by the engine
the greenhouse effect
the good conducting power of the metal body
the double layered wind shield
When an electric apparatus is fitted with a three core flexible lead the insulation on the three wires is distinctively coloured. The present international convention is
brown for earth, yellow for live, light blue for neutral
green for earth, yellow for live, brown for neutral
yellow for earth, green for live, brown for neutral
brown or red for live, light blue or black for neutral and green or yellow for earth
When we sweat, we feel comfortable under a fan because
the air circulated by the fan is cool
the fan produces convection currents of air
the air circulated by the fan quickens the evaporation of the moisture on our skin
the air takes away the heat from our body
The velocity of sound in air increases with
the rise of temperature
rise of its frequency
decrease in humidity
fall of temperature
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
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
In a refrigerator, the refrigerant is
Nitrogen
Oxygen
Chlorine
Freon
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
Primary colours are
colours of the rainbow
colours in the spectrum of white light
colours which cannot be produced by mixing other colours
colours found in nature
The evaporation rate depends on
the nature of the liquid
area of the exposed surface of the liquid
temperature of air and of the liquid
All the above
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
The characteristics of a musical note are
loudness
pitch
quality or timbre
All the above
A spherical mirror is
a reflecting elliptical portion
a reflecting spherical surface
a parabolic reflecting surface
a flat reflecting surface
Enriched uranium means
Uranium that is very pure
Uranium in which the concentration of the isotope U-238 is more than in the naturally occuring uranium
Uranium in which the concentration of the isotope U-235 is more than in the naturally occuring uranium
None of the above
During thunder storm you are travelling in a car. To protect yourself from the lightning you will have to
remain in the car
get out of the car and lie flat in the ground
abandon the car and take shelter under a nearby tree
touch the nearest electric pole
Warm air will hold more water vapour than cold air because
it is lighter
it has more water vapour in it
its molecules are close together
its molecules are far apart
In the electrical circuit of a house the fuse acts as
a thermopile
a load
a step down device
a safety device
Which of the following is not electromagnetic waves?
heat waves
sound waves
radio waves
light waves
To produce beats it is necessary to have two waves
travelling in opposite direction
of slightly different frequencies
of equal wavelength
of equal amplitude
Light from the sun reaches the earth in
2 minutes
4 minutes
12 minutes
8 minutes