Waves Test - 10...

Assertion Sound waves cannot propagate through vacuum but light waves can.
ReasonSound waves cannot be polarised but light waves can be polarised.

AssertionThe change in air pressure effects the speed of sound.
Reason The speed of sound in gases is proportional to the square of pressure.

Assertion The reverberation time dependent on the shape of enclosure, position of source and observer.
Reason The unit of absorption coefficient in MKS system is metric sabine.

Assertion When a beetle moves along the sand with in a few tens of centimeters of a sand scorpion the scorpion immediately turn towards the beetle and dashes to it.
Reason When a beetle disturbs the sand, it sends pulses along the sands surface one set of pulses is longitudinal while other set is transverse.

Assertion Transverse waves travel through air in an organ pipe.
Reason Air possesses only volume elasticity.

Assertion Sound would travel faster on a hot summer day than on a cold winter day.
Reason Velocity of sound is directly proportional to the square of its absolute temperature.

Assertion The basic of Laplace correction was that, exchange of heat between the region of compression and rarefaction in air is not possible.
Reason Air is a bad conductor of heat and velocity of sound in air is large.

Assertion Particle velocity and wave velocity both are independent of time.
Reason For the propagation of wave motion, the medium must have the properties of elasticity and inertia.

Assertion The flash of lightening is seen before the sound of thunder is heard.
Reason Speed of sound is greater than speed of light.

Assertion A tuning fork is made of an alloy of steel, nickel and chromium.
Reason The alloy of steel, nickel and chromium is called elinvar.