Question

170. A tuning fork 512 Hz is used to pro-
duce 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. The error in cal-
culating velocity of sound is (Speed of
sound in air = 330 m/s)
1) 204.1 cm/s
2) 110 cm/s
3) 58 cm/s
4)280 cm/s​

Answer 1

Explanation:

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 = Vo = fλ = 332.8 m/s ∴ error observed = Vo – 330 = 332.8 – 330 = 2.8 m/s error = 2.8 m/s

when,, 2.8m/s =280cm/s

Answer 2

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 = Vo = fλ = 332.8 m/s

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

∴ error = 2.8 m/s = 280 cm/s