Q. A resonance air column of length $20\ cm$ resonated with a tuning fork of frequency $250\ Hz.$ The speed of sound in air is
A) $300\ m/s$
B) $200\ m/s$
C) $150\ m/s$
D) $75\ m/s$
Explanation
(b) For closed pipe $n_{1} = \frac{v}{4l} \Rightarrow 250 = \frac{v}{4 \times 0.2} \Rightarrow v = 200m/s$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.