A pipe closed at one end has length 83 cm. The number of possible natural oscillations of air column whose frequencies lie below 100Hz are (velocity of sound in air = 332 m/s)
A pipe closed at one end has length 83 cm. The number of possible natural oscillations of air column whose frequencies lie below 100Hz are (velocity of sound in air = 332 m/s)
  1. 0
  2. 4
  3. 5
  4. 6

Solution: The correct answer is A. 0

The frequency for a pipe closed at one end is given by:

f = (n×v )/4L   
v = speed of sound = 332m/s
L = length of pipe = 83cm = 0.83m
n = 0,1,2…
f = (1×332)/(4×0.83)
f = 100Hz
Hence, no natural oscillation of frequency less than 100Hz.