The length of a closed and an open pipe is the same. The ratio of the frequency of the $n^{\text{th}}$ overtone for the closed pipe to that of the open pipe is (Neglect end correction).

The fundamental frequency of an open pipe of length $0.5 \ m$ is equal to the frequency of the first overtone of a closed pipe of length $l_c$. The value of $l_c$ in meters is:

$A$ closed pipe is suddenly opened and changed to an open pipe of the same length. The fundamental frequency of the resulting open pipe is less than that of the $3^{rd}$ harmonic of the earlier closed pipe by $55 \,Hz$. Then, the value of the fundamental frequency of the closed pipe is: (in $\,Hz$)

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).

In a closed organ pipe,the frequency of the fundamental note is $30 \,Hz$. $A$ certain amount of water is now poured into the organ pipe so that the fundamental frequency increases to $110 \,Hz$. If the organ pipe has a cross-sectional area of $2 \,cm^2$,the amount of water poured into the organ tube is . . . . . . $g$. (Take the speed of sound in air as $330 \,m/s$)

$A$ source of frequency $340 \,Hz$ is kept above a vertical cylindrical tube closed at the lower end. The length of the tube is $120 \,cm$. Water is slowly poured in just enough to produce resonance. Then, the minimum height (velocity of sound $= 340 \,m/s$) of the water level in the tube for that resonance is (in $\,m$)