Two closed organ pipes having lengths $20\,cm$ and $20.5\,cm$ produce $5\,beats/sec$. Determine the frequency of both organ pipes.

The length of an open organ pipe is twice the length of a closed organ pipe. The fundamental frequency of the open pipe is $100 \ Hz$. The frequency of the third harmonic of the closed pipe is: (in $Hz$)

The fundamental frequency of an open pipe is $100 \ Hz$. If the bottom end of the pipe is closed and $1/3$ rd of the pipe is filled with water,then the fundamental frequency of the pipe is: (in $Hz$)

$A$ metal rod of length $125 \ cm$ is clamped at its midpoint. If the speed of sound in the metal is $5000 \ ms^{-1}$, then the fundamental frequency of the longitudinal vibrations of the rod is (in $kHz$)

$A$ flute,which we treat as a pipe open at both ends,is $34\, cm$ long. The fundamental frequency of the flute when all its holes are covered is .... $Hz$ [Take velocity of sound in air $= 340\, m/s$].

For a certain organ pipe,the first three resonance frequencies are in the ratio of $1:3:5$ respectively. If the frequency of the fifth harmonic is $405 \, Hz$ and the speed of sound in air is $324 \, ms^{-1}$,the length of the organ pipe is $.......... m$.