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 |
Which of the following statement is correct?
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 on the inertia property |
2. | the inertia property but not on the elastic property |
3. | the elastic property as well as the inertia property |
4. | neither the elastic property nor the inertia 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. |
A rope of uniform mass per unit length \(\mu\) is suspended from the ceiling, hanging under its own weight. If a small transverse pulse is formed at its lower end A, it travels upward with a local speed \(v=\sqrt {\dfrac{\text{tension}}{\text{mass/length}}}\).
The speed of the pulse is:
1. | maximum at A, minimum at O |
2. | minimum at A, maximum at O |
3. | uniform |
4. | minimum at A and O, maximum in the middle |
The intensity \((I)\) of a sound wave depends on the distance \((x)\) from the source as:
1. \(I\propto x\)
2. \(I\propto \frac1x\)
3. \(I\propto \frac1{x^2}\)
4. None of the above
The separation between a node and the next antinode in a vibrating air column is \(20\) cm. The speed of sound is \(320\) m/s. The frequency of sound is:
1. \(128\) Hz
2. \(256\) Hz
3. \(400\) Hz
4. \(800\) Hz