Speed of sound in air at standard temperature and pressure is:
(Given the mass of \(1\) mole of air is \(29.0\times10^{-3}\) kg and \(\gamma=7/5 \text)\)
1. \(240 \) m/s
2. \(331.5\) m/s
3. \(384.5\) m/s
4. \(280\) m/s
A steel wire \(0.72~\text{m}\) long has a mass of \(5\times10^{-3}~\text{kg}\). If the wire is under tension of \(60~\text{N}\), the speed of transverse waves on the wire will be:
1. \(85~\text{m/s}\)
2. \(83~\text{m/s}\)
3. \(93~\text{m/s}\)
4. \(100~\text{m/s}\)
A wave travelling along a string is described by, \(y(x,~t)=0.005 ~\sin(80.0x-3.0t),\) in which the numerical constants are in SI units. The displacement \(y\) of the wave at a distance \(x = 30.0\) cm and time \(t=20\) s is:
1. \(0.5\) mm
2. \(5\) mm
3. \(5\) m
4. \(5\) cm
Which of the following is a mechanical wave?
1. | Radio waves | 2. | X-rays |
3. | Light waves | 4. | Sound waves |
Two strings \(A\) and \(B,\) made of same material, are stretched by same tension. The radius of string \(A\) is double of the radius of \(B.\) A transverse wave travels on \(A\) with speed \(v_A\) and on \(B\) with speed \(v_B.\) The ratio \(\frac{v_A}{v_B}=\) ?
1. | \(\frac{1}{2}\) | 2. | \(2\) |
3. | \(\frac{1}{4}\) | 4. | \(4\) |
Velocity of sound in air is \(332\) m/s. Its velocity in the vacuum will be:
1. \(>332\) m/s
2. \(=332\) m/s
3. \(<332\) m/s
4. meaningless
A wave moving in a gas:
1. | must be longitudinal | 2. | may be longitudinal |
3. | must be transverse | 4. | may be transverse |
1. | The energy of any small part of a string remains constant in a travelling wave. |
2. | The energy of any small part of a string remains constant in a standing wave. |
3. | The energies of all the small parts of equal length are equal in a travelling wave. |
4. | The energies of all the small parts of equal length are equal in a standing wave. |
The speed of sound in a medium depends on:
1. | the elastic property but not the inertial property |
2. | the inertial property but not the elastic property |
3. | both the elastic and inertial properties |
4. | neither the elastic property nor the inertial property |
Assertion (A): | Sound waves in a gas are pressure waves, but these are also accompanied by changes in local temperature. |
Reason (R): | This is due to the fact that sound waves are propagated in gas through an adiabatic process, and hence accompanied by temperature variations. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |