Q 11-14-019NEETJEE MainMedium
In a resonance tube experiment with a $512$ Hz fork, the first and second resonances occur at air-column lengths of $16$ cm and $49$ cm. The speed of sound in air is
Answer: (C) $337.9$ m/s
Concept. Successive resonance lengths differ by $\dfrac{\lambda}{2}$; using the difference removes the end correction.
Step 1. Wavelength. $\dfrac{\lambda}{2} = 49 - 16 = 33$ cm, so $\lambda = 0.66$ m.
Step 2. Speed. $v = 512 \times 0.66 \approx 337.9$ m/s.
Answer. $337.9$ m/s (Option C).
Solution by Sreeraj P, M.Sc Physics