The fundamental frequency of a closed organ pipe is equal to the first overtone frequency of an open organ pipe. If the length of the open pipe is 60 cm, what is the length closed pipe?

Explanation

The fundamenrtal frequency of a closed orgain pipe is v/(4l_1)`. For an open pipe, the fundamental frequency is `v/(2l_2)` and the first overtone is `(2v)/(2l_2)=v/l_2`. Here `l_1` is the length of the closed pipe and `l_2=60` cm is the length of the open pipe. We have
`v/(4l_1)=v/(60cm)`
`l_1=1/4xx60cm=15cm`.