A standing wave is produced on a string clamped at one end and free at the other. The length of the string:
1. | must be an integral multiple of \(\frac{\lambda}{4}\) |
2. | must be an integral multiple of \(\frac{\lambda}{2}\) |
3. | must be an integral multiple of \(\lambda\) |
4. | may be an integral multiple of \(\frac{\lambda}{2}\) |
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. |
In a stationary wave,
(a) all the particles of the medium vibrate in phase
(b) all the antinodes vibrate in phase
(c) the alternate antinodes vibrate in phase
(d) all the particles between consecutive nodes vibrate in phase
Choose the correct option:
1. (a) and (b)
2. (b) and (c)
3. (c) and (d)
4. all of these
Consider the following statements about sound passing through a gas.
A: | The pressure of the gas at a point oscillates in time. |
B: | The position of a small layer of the gas oscillates in time. |
1. | Both A and B are correct. |
2. | A is correct but B is wrong. |
3. | B is correct but A is wrong. |
4. | Both A and B are wrong. |
When we clap our hands, the sound produced is best described by
(Here p denotes the change in pressure from the equilibrium value)
1. p = p0 sin(kx – ωt)
2. p = p0 sin kx cos ωt
3. p = p0 cos kx sin ωt
4. p = \(\sum\)p0n sin(knx – ωnt)
The bulk modulus and the density of water are greater than those of air. With this much of information, we can say that velocity of sound in air
1. is larger than its value in water
2. is smaller than its value in water
3. is equal to its value in water
4. cannot be compared with its value in water
A tuning fork sends sound waves in the air. If the temperature of the air increases, which of the following parameters will change?
1. Displacement amplitude
2. Frequency
3. Wavelength
4. Time period
When sound wave is refracted from air to water, which of the following will remain unchanged?
1. Wave number
2. Wavelength
3. Wave velocity
4. Frequency
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 |
Two sound waves move in the same direction in the same medium. The pressure amplitudes of the waves are equal but the wavelength of the first wave is double the second. Let the average power transmitted across cross-section by the first wave be \(P_1\) and that by the second wave be \(P_2.\) Then:
1. | \(P_1=P_2~~~~~\) | 2. | \(P_1=4P_2~~~~~\) |
3. | \(P_2=2P_1\) | 4. | \(P_2=4P_1\) |