Question

A tuning fork of frequency $520\, Hz$ is used in an experiment for measuring speed of sound (v) in air by resonance tube method. Resonance is observed to occur at two successive lengths of the air column, $l_{1}=40\, cm$ and $l_{2}=70\, cm$. The value of $y \left(\right.$ in $\left.ms ^{-1}\right)$ is equal to______

Answer 1

Given, frequency of tuning fork $=520\, Hz$
Resonance lengths, $l_{1}=40$ and $l_{2}=70\, cm$
Speed of sound, $v_{\text {air }}$
$=2 v\left(l_{2}-l_{1}\right)$
$=2 \times 520 \times(70-40) \times 10^{-2}$
$=1040 \times 30 \times 10^{-2}$
$=312\, ms ^{-1}$