Q. In a resonance tube, using a tuning fork of frequency 325 Hz, two successive resonance lengths are observed as 25.4 cm and 77.4 cm respectively. The velocity of sound in air is
A) $338\ ms^{- 1}$
B) $328\ ms^{- 1}$
C) $330\ ms^{- 1}$
D) $320\ ms^{- 1}$
Explanation
(a) $Velocity\ of\ sound\ in\ air\ v = 2n\left( l_{2} - l_{1} \right)$
$= 2 \times 325(77.4 - 25.4)$
$= \frac{650/52}{100}$
=338 m/s
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.