A 500 Hz tuning fork produces two successive resonances in a resonance tube at air-column lengths 16 cm and 50 cm. Assuming the same end correction at both resonances, if the speed of sound is N m/s, find N.
Physics · Wave Motion · Standing Sound Waves, Organ Pipes and Resonance Tubes
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Question

A 500 Hz tuning fork produces two successive resonances in a resonance tube at air-column lengths 16 cm and 50 cm. Assuming the same end correction at both resonances, if the speed of sound is N m/s, find N.

Physics · Wave Motion · Standing Sound Waves, Organ Pipes and Resonance Tubes

G1 Physics · Accepted Answer

For successive resonance lengths, l₂−l₁ = λ/2. Therefore, λ = 2(l₂−l₁) = 2(50−16) cm = 68 cm = 0.68 m. Wave speed is v = fλ = 500×0.68 = 340 m/s. Hence, N = 340.