Two sitar strings A and B playing the note 'Ga' are slightly out of tune and produce beats of frequency 6 Hz. The tension in the string A is slightly reduced and the beat frequency is found to reduce to 3 Hz. If the original frequency of A is 324 Hz, what is the frequency of B?

Explanation

Frequency of string A = 324 Hz = `n_(a)`
Freqency of string B = `n_(b) = ?`
No. of beats/sec. = 6
`n_(b) = n_(a) +- 6`
`= 324 +- 6` either 330 Hz or 318 Hz
As when tension is reduced, beat frequency also reduces `(because v prop sqrt(T))`
Thus if orginal frequency of A is 324 Hz then the frequency of B cannot be 330 Hz.
Therefore, frequency of B = 318 Hz