The first overtone frequency of a closed organ pipe P1 is equal to the fundamental frequency of an open organ pipe P2. If the length of the pipe P1 is 30 cm, what will be the length of P2?
Given:
Length of closed organ pipe L1 = 30 cm
Length of open organ pipe L2 =?
Let and
be the frequencies of the closed and open organ pipes, respectively.
The first overtone frequency of a closed organ pipe P1 is given by
Where v is the speed of sound in air.
On substituting the respective values, we get:
Fundamental frequency of an open organ pipe is given by:
As per the question,
∴ the length of the pipe P2 will be 20 cm.