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
Correct Answer :
A. the same as the direction of the vibrations of the vibrating body
Related Questions
Halley's comet appears in the heavens once in
40 years
50 years
76 years
80 years
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
In an oil lamp, holes are provided below the chimney so that
necessary oxygen for burning of oil may be provided
the convection current of air may be maintained to keep the lamp burning
the brightness of the lamp may be increased
All the above
The nuclear model of atom was first visualised by
Rutherford
Neils Bohr
Albert Einstein
JJ Thompson
Solids have definite shapes. This is because
the forces of cohesion of the molecules within are very much less in them
the forces of cohesion are very large
the forces of adhesion are large
the forces of adhesion are less
Why is it cool near an open pond on a hot summer day?
Evaporation at the surface causes cooling
The heat obsorbed at the surface is passed on to the bottom
Because of impurity in the water
Because of convection currents set up inside water
The ozone layer absorbs
Cosmic rays
Infrared rays
All radiations of light
Ultra violet rays coming from the sun
In experiments on static electricity the standard method for obtaining small amounts of positive electricity is to rub
a glass rod with flannel
an abonite rod with flannel
a glass rod with silk
Any of the above
Which of the following wires of same dimensions offers least resistance to the ,flow of current?
copper
aluminium
silver
nichrome
A permanent magnet may be demagnetised by
placing it inside a solenoid through which an alternating current is flowing
heating the magnet to redness and then allowing it to cool
dropping it several times or hammering it while lying east-west
All the above
In a freezer ice cubes will be formed more quickly in trays made of
rubber
plastic
aluminium
wood
Sound travels fastest in
air
water
iron
vacuum
If you want to open a door with les difficulty you push it
at the middle
at a point away from the hinge (near the rim)
near the hinge
None of the above
A projectile is fired at an angle with the horizontal with a small velocity. Its horizontal range will be maximum when the angle with the horizontal is
0°
30°
45°
60°
Besides protons, the nucleus of an atom contains
electrons
neutrons
neutrons and electrons
electrons, neutrons and other particles
A bar magnet tied in the middle with a thread is suspended at the South Pole of the earth. The magnet will be in
a horizontal position
a nearly vertical position with its South Pole downwards
a nearly vertical position with its North Pole downwards
a slanting position
The speed of sound in air at 0° C is approximately
4 x 10 8 m/s
1500 m/s
330 m/s
500 m/s
A timer in a race is at the finish line. He should start his stop watch
as soon as he hears the report of the gun
the moment he sees the flash
either (a) or (b) since that makes no difference
None of the above
Solar radiation is preferred to other sources of energy because
it is practically inexhaustible
it is the cheapest form of energy
it does not cause pollution
All of the above
A nuclear reactor is said to have become 'critical' when
it stops due to malfunctioning
it starts emitting dangerous radioactive radiations
it is shut down to avoid explosion
it is ready to produce controlled energy
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
A workman was working on a rail track. A young boy at a distance holds his ear close to the railway track. The boy was able to hear the sound of each blow or the workman twice. It is because
speed of sound is greater in steel than in air
speed of sound is greater in air than in steel
part of sound waves is reflected between rail tracks
the boy's ears are at a different distance from the source
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
In compact porous soil, the rising of the water is due to
capillarity
cohesion
adhesion
viscosity
Which part of the eye photographic camera?
Lens
Iris
Retina
Eyelid
The largest planet in the solar system is
Neptune
Uranus
Jupiter
Saturn
An electric charge is measured in
coulomb
ampere
volt
watt
Mercury is used in thermometers because
it has high thermal conductivity
it has uniform expansivity
it has high boiling point and low freezing point
of all the above
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
A convex mirror always produces
an erect, virtual image of diminished size
an erect, real image of diminished size
an erect, real image of double size
a virtual image of double size