WAEC - Physics (1992 - No. 38)
A pipe closed at one end is 1.0m long. The air in the pipe is set into vibration and a fundamental note of frequency 85Hz is produced. Calculate the velocity of sound in the air. (Neglect end correction).
340.0ms-1
33Oms-1
170ms-1
85.0ms-1
42.5ms-1
Vysvětlení
L = λ/4; λ= 4 = 4m
v = fλ = 85 x 4 = 340ms-1
v = fλ = 85 x 4 = 340ms-1