Two closed pipes produce $10$ beats per second when emitting their fundamental notes. If their lengths are in the ratio of $25 : 26$,then their fundamental frequencies in $Hz$ are:

$A$ closed organ pipe and an open organ pipe have the same length $L$. When they are vibrating simultaneously in their first overtone,they produce $3$ beats per second. If the length of the open pipe is reduced to $\frac{1}{3}$ of its original length and the length of the closed pipe is increased to $3$ times its original length,calculate the number of beats produced per second. (Neglect end correction)

$A$ closed organ pipe of radius $r_1$ and an open organ pipe of radius $r_2$ having the same length $L$ resonate when excited with a given tuning fork. The closed organ pipe resonates in its fundamental mode,whereas the open organ pipe resonates in its first overtone. Then:

An open air pipe of length $80 \,cm$ has the second harmonic frequency equal to the fundamental frequency of a closed organ air pipe. The length of the closed pipe is (in $\,cm$)

The number of possible natural oscillations of an air column in a pipe closed at one end of length $85 \, cm$ whose frequencies lie below $1250 \, Hz$ are (Velocity of sound $= 340 \, m s^{-1}$)

Find the fundamental frequency of a closed pipe,if the length of the air column is $42 \, m$. (speed of sound in air $= 332 \, m/s$) (in $, Hz$)