41. If the velocity of sound in
liquid is much greater than that in a gas, then why don't a
person under water unable to listen to someone speaking in air?
the water is a good absorber good reflector and good
damper so when sound waves incident on the surface of
water, some parts of waves are reflected by it and some
is absorbed but a very small amount is left for the
propagation which when propagated through water dies out
quickly due to damping. Hence, a person
under water unable to listen to someone speaking in air
even if the velocity of sound in liquid is much greater
than that in a gas.
42. Velocity of sound in hydrogen is
greater than that in oxygen why?
the constant pressure and temperature, the velocity
of the sound varies inversely to the square root of
its density i.e.
where, v is
the velocity of the sound in air and
is the density of gas.
density of oxygen gas is greater than that of the
hydrogen, the velocity of sound in hydrogen is greater
than that of the oxygen.
43. Which is the most fundamental property of a wave?
44. Why are stationary waves called so?
45. What causes the rolling sound of a thunder?
46. A closed earthen vessel (Surai) is gives. Can we
distinguish when the vessel is filled or empty without
lifting it and looking inside. Justify your answer.
47. Differentiate between forced vibration and free