Question

The wind blows across a small cave and creates a moaning sound. The cave is 6.2m deep and the temperature is 5 degres C. Calculate the fundamental frequency.

Answer 1

The cave will behave like a pipe closed at one end.

So, in the fundamental mode

  

Given L = 6.2 m

So,   

We know that ,

Where, v is speed of sound in air at 5 degrees C which is 334.32 m/s.

f is fundamental frequency

   is wavelength

So,

This is the fundamental frequency.

For any doubt please comment and please give an up-vote.Thank you.