Question

A tuning fork of frequency $512Hz$ is vibrated with a sonometer wire and $6$ beats per second are heard. The beat frequency reduces if the tension in the string is slightly increased. The original frequency of vibration of the string is

• A. $506Hz$
• B. $512Hz$
• C. $518Hz$
• D. $524Hz$

Answer 1

Answer: (A)

$506Hz$

$v_2$ could be $518Hz$ or $506Hz$ for $6$ beats/ second. If the tension of the sonometer wire is slightly increased, $v_2$ increases, but the beat reduces, therefore the original frequency of the string is $506Hz$.