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
Correct Answer :
A. lowers the melting point of ice
Related Questions
Chronometer la an instrument to measure
heat
electric potential
time
distance between two points
Which of the following sets of elementary particles have nearly equal masses?
Neutron and Proton
Electron and Proton
Neutron and Electron
Proton, Neutron and Electron
A person does not sink in the Dead Sea because
the sea contains a large amount of other salts besides sodium chloride
the density of the person is less than the density of the Dead Sea water
of the surface tension due to salt water in the Dead Sea
of difference in mass
When ice melts, Its volume
decreases
increases
remains the same until all the ice has melted and then increases
remains the same
The device that is used to measure the electromotive force of a cell is
an ammeter
a rheostat
a voltmeter
a voltameter
Match the following:
| A. Anemometer | 1. Measurement of power |
| B. Tachometer | 2. Wind speed |
| C. Dynamometer | 3. Revolutions per minute |
| D. Barometer | 4. Atmospheric pressure |
| * | 5. Current from a dynamo |
A-1 B-3 C-5 D-4
A-2 B-1 C-3 D-4
A-2 B-3 C-1 D-4
A-1 B-3 C-5 D-2
Compared to the atomic bomb, the destructive power of a hydrogen bomb is
greater
less
equal
can't be determined
When a bottle of perfume la opened in one corner of a room the smell spreads soon throughout the room. This is an example of
surface tension
capillarity
viscosity
diffusion
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
In a longitudinal wave, the direction of propagation of the wave is
the same as the direction of the vibrations of the vibrating body
at right angles to the direction of the vibrations of the vibrating body
Both (a) and (b) above
None of the above
Photo-electric cells convert
electrical energy into light energy
light energy into electrical energy
light energy into heat energy
electrical energy into heat energy
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
The rings of Saturn were discovered by
Galileo
Bhaskara
Aryabhatta
Ptolemy
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
An ammeter has
a high resistance
a very low resistance
no resistance at all
resistance of 400 � w
The stars that shine brightly then dimly and then brightly are known as
meteors
binaries
variable stars
bright stars
The attraction of unlike molecules at the common surface is known as
adhesion
cohesion
surface tension
capillarity
The maximum displacement of the particle in a mechanical wave motion is known as
amplitude
vibration
frequency
phase
In a freezer ice cubes will be formed more quickly in trays made of
rubber
plastic
aluminium
wood
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
The rate of cooling of a hot body depends on
the nature of the radiating surface
area of the radiating surface
temperature difference between the body and the surroundings
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 light from the star nearest to the sun reaches the earth in
8 minutes
4.3 years
12 seconds
24 hours
The Milky Way is
the path of a star which is nearest to the earth
a galaxy which includes the sun
a star that is nearest to the earth
None of these
We always see only one side of the moon because
the sun comes in between the earth and moon
the moon is stationary
the time taken by the moon to rotate on its axis is the same as the time taken by it to revolve round the earth
moon revolves round the sun
Less dew is formed on cloudy nights because
there is no moisture in the atmosphere
clouds absorb the falling dew
objects emit radiant energy very fast on such nights
objects lose less radiant energy
The loudness of a sound is determined by
Frequency
Amplitude
Speed
Wavelength
Raindrops assume a spherical shape because or
adhesion
surface tension
gravitational force
atmospheric pressure from all sides
The hygrometer is an apparatus used for finding the
temperature of air
intensity of light
density of a liquid
relative humidity of the atmosphere
Under similar conditions of temperature and pressure, the velocity of sound is maximum in
helium
argon
hydrogen
oxygen