Two sitar strings, \(A\) and \(B,\) are tuned to play the same note (“Dha”), but are slightly out of tune and produce beats of frequency \(5~\text{Hz}.\) When the tension in string \(B\) is slightly increased, the beat frequency decreases by \(3~\text{Hz}.\) If the frequency of string \(A\) is \(425~\text{Hz},\) what was the original frequency of string \(B\text{?}\)
1. \(428~\text{Hz}\)
2. \(430~\text{Hz}\)
3. \(422~\text{Hz}\)
4. \(420~\text{Hz}\)
Subtopic:  Beats |
 63%
Level 2: 60%+
Please attempt this question first.
Hints
Please attempt this question first.

The correct figure that shows, schematically, the wave pattern produced by the superposition of two waves of frequencies \(9~\text{Hz}\) and \(11~\text{Hz}\), is:

1.
2.
3.
4.
Subtopic:  Beats |
Level 3: 35%-60%
JEE
Please attempt this question first.
Hints
Please attempt this question first.

A tuning fork \(\mathrm A\) of unknown frequency produces \(5\) beats per second with a fork of known frequency of \(340\) Hz. When fork \(\mathrm A\) is filed, the beat frequency decreases to \(2\) beats per second. What is the frequency of fork \(\mathrm A\)?

1. \(342\) Hz 2. \(345\) Hz
3. \(335\) Hz 4. \(338\) Hz
Subtopic:  Beats |
 56%
Level 3: 35%-60%
JEE
Please attempt this question first.
Hints
Please attempt this question first.

advertisementadvertisement

A set of \(20\) tuning forks is arranged in a series of increasing frequencies. If each fork gives \(4\) beats with respect to the preceding fork and the frequency of the last fork is twice the frequency of the first, then the frequency of the last fork is:
1. \(152~\text{Hz}\)
2. \(234~\text{Hz}\)
3. \(134~\text{Hz}\)
4. \(144~\text{Hz}\) 
Subtopic:  Beats |
 76%
Level 2: 60%+
JEE
Hints

The velocity of sound in a gas in which two wavelengths \(4.08\) m and \(4.16\) m produce \(40\) beats in \(12\) s, will be:
1. \(282.8\) ms–1
2. \(175.5\) ms–1
3. \(353.6\) ms–1
4. \(707.2\) ms–1
Subtopic:  Beats |
 67%
Level 2: 60%+
JEE
Please attempt this question first.
Hints
Please attempt this question first.