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 $.......... m$.

$A$ resonance air column of length $20 \ cm$ resonates with a tuning fork of frequency $250 \ Hz$. The speed of sound in air is .... $m/s$.

$A$ person blows into the open end of a long pipe. As a result,a high-pressure pulse of air travels down the pipe. When this pulse reaches the other end of the pipe:

At $23^{\circ} C$,a pipe open at both ends resonates at a frequency of $450 \,Hz$. At what frequency does the same pipe resonate on a hot day when the speed of sound is $4 \%$ higher than it would be at $23^{\circ} C$ (in $,Hz$)?

In an experiment to determine the velocity of sound in air at room temperature using a resonance tube,the first resonance is observed when the air column has a length of $20.0 \,cm$ for a tuning fork of frequency $400 \,Hz$. The velocity of sound at room temperature is $336 \,ms^{-1}$. The third resonance is observed when the air column has a length of ......... $cm$.

While measuring the speed of sound by performing a resonance column experiment,a student gets the first resonance condition at a column length of $18 \ cm$ during winter. Repeating the same experiment during summer,she measures the column length to be $x \ cm$ for the second resonance. Then