A pipe closed at one end has a length of 83 cm. The number of possible natural oscillations of air column whose frequencies lie below 1000 Hz are (take, the velocity of sound in air =332 m/s)

A) 3

B) 4

C) 5

D) 6


Option C


Fundamental freequency of one  end closed pipe,


 Here, n=1

 or   $v_{1}=\frac{332}{4\times 83\times 10^{-2}}$

 or v1  = 100

As  odd harmonics alone are produced in closed organ  pipe, therefore  possible frequencies are

    3v1 =300 Hz. 5 v2 =500 Hz

  7 v2 = 700 hz , 9 v2 =900 Hz

 Hence, the number of the possible natural oscillation of air column is 5