The lengths of two open organ pipes are $l$ and $(l + \Delta l)$ respectively. Neglecting end correction,the frequency of beats between them will be approximately (Here $v$ is the speed of sound).

$A$ cylindrical tube,open at both ends,has a vibrating air column of fundamental frequency '$f$' in air. The tube is dipped vertically in water so that half of its length is in water. The fundamental frequency of the vibrating air column is now:

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

$A$ cylindrical tube open at both ends has a fundamental frequency $f$ in air. The tube is dipped vertically in water so that $60 \%$ of the tube is in water. Then the fundamental frequency of the air column is

$A$ pipe open at both ends of length $1.5 \ m$ is dipped in water at one end such that the $2^{\text{nd}}$ overtone of the vibrating air column is resonating with a tuning fork of frequency $330 \ Hz$. The length of the pipe immersed in water is (Speed of sound in air $= 330 \ m/s$) (Neglect end correction). (in $m$)

The fundamental frequency of an open pipe is $n$. If it is closed from one end, then the frequency of the $2^{nd}$ harmonic of the closed pipe is higher by $200 \,Hz$ than $n$. The value of $n$ is: (in $\,Hz$)