Question

A tuning fork of 512 Hz is used to produce resonance in a resonance tube experiment. The level of water at first resonance is 30.7 cm and at second resonance is 63.2 cm. What is the error in calculating velocity of sound? Assume the speed of sound 330 m/s. 

(A) 58 (cm / s) 

(B) 204.1 (cm / s) 

(C) 280 (cm / s) 

(D) 110 (cm / s)

Answer 1

The correct option is (C) 280 (cm / s).

Explanation:

f = 512 Hz 

In first resonance, length = 30.7 cm 

In second resonance length = 63.2 cm 

(λ/2) = (63.2 – 30.7)cm 

∴ (λ/2) = 32.5 

∴ λ = 65 cm = 0.65 cm 

velocity of sound = V_o = fλ = 332.8 m/s 

∴ error observed = V_o – 330 = 332.8 – 330 = 2.8 m/s 

∴ error = 2.8 m/s = 280 cm/s