A source of unknown frequency gives \(4\) beats/s when sounded with a source of known frequency of \(250~\text{Hz}.\) The second harmonic of the source of unknown frequency gives five beats per second when sounded with a source of frequency of \(513~\text{Hz}.\) The unknown frequency will be:
| 1. | \(246~\text{Hz}\) | 2. | \(240~\text{Hz}\) |
| 3. | \(260~\text{Hz}\) | 4. | \(254~\text{Hz}\) |
A wave traveling in the +ve \(x\text-\)direction having maximum displacement along \(y\text-\)direction as \(1~\text{m}\), wavelength \(2\pi~\text{m}\) and frequency of \(\frac{1}{\pi}~\text{Hz}\), is represented by:
| 1. | \(y=\sin (2 \pi x-2 \pi t)\) | 2. | \(y=\sin (10 \pi x-20 \pi t)\) |
| 3. | \(y=\sin (2 \pi x+2 \pi t)\) | 4. | \( y=\sin (x-2 t)\) |
When a string is divided into three segments of lengths \(l_1\), \(l_2\) and \(l_3\), the fundamental frequencies of these three segments are \(\nu_1\), \(\nu_2\) and \(\nu_3\) respectively. The original fundamental frequency (\(\nu\)) of the string is:
| 1. | \(\sqrt{\nu} = \sqrt{\nu_1}+\sqrt{\nu_2}+\sqrt{\nu_3}\) |
| 2. | \(\nu = \nu_1+\nu_2+\nu_3\) |
| 3. | \(\dfrac{1}{\nu} =\dfrac{1}{\nu_1} +\dfrac{1}{\nu_2}+\dfrac{1}{\nu_3}\) |
| 4. | \(\dfrac{1}{\sqrt{\nu}} =\dfrac{1}{\sqrt{\nu_1}} +\dfrac{1}{\sqrt{\nu_2}}+\dfrac{1}{\sqrt{\nu_3}}\) |
Two sources of sound placed close to each other, are emitting progressive waves given by,
\(y_1=4\sin 600\pi t\) and \(y_2=5\sin 608\pi t\).
An observer located near these two sources of sound will hear:
| 1. | \(4\) beats per second with intensity ratio \(25:16\) between waxing and waning |
| 2. | \(8\) beats per second with intensity ratio \(25:16\) between waxing and waning |
| 3. | \(8\) beats per second with intensity ratio \(81:1\) between waxing and waning |
| 4. | \(4\) beats per second with intensity ratio \(81:1\) between waxing and waning |
| 1. | increase by a factor of \(20\). |
| 2. | increase by a factor of \(10\). |
| 3. | decrease by a factor of \(20\). |
| 4. | decrease by a factor of \(10\). |
A transverse wave is represented by y = Asin(ωt -kx). At what value of the wavelength is the wave velocity equal to the maximum particle velocity?
1. A/2
2. A
3. 2A
4. A
A tuning fork of frequency \(512~\text{Hz}\) makes \(4~\text{beats/s}\) with the vibrating string of a piano. The beat frequency decreases to \(2~\text{beats/s}\) when the tension in the piano string is slightly increased. The frequency of the piano string before increasing the tension was:
1. \(510~\text{Hz}\)
2. \(514~\text{Hz}\)
3. \(516~\text{Hz}\)
4. \(508~\text{Hz}\)
| 1. | \(5\) | 2. | \(7\) |
| 3. | \(8\) | 4. | \(3\) |