$A$ tuning fork of frequency $340\, Hz$ is vibrated just above a tube of $120\, cm$ height. Water is poured slowly into the tube. What is the minimum height of water necessary for resonance? (Speed of sound in air $= 340\, m/s$)

$A$ closed organ pipe of length $L_1$ and an open organ pipe contain diatomic gases of densities $\rho_1$ and $\rho_2$ respectively. The compressibilities of the gases are same in both pipes,which are vibrating in their first overtone with the same frequency. The length of the open organ pipe is (Neglect end correction).

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 $Hz$)

What kind of figures are possible for a closed pipe?

The closed and open organ pipes have the same length $L$. When they are vibrating simultaneously in their first overtone,they produce $4$ beats per second. The length of the open pipe is made half $(L/2)$ and that of the closed pipe is made two times $(2L)$ the original. Now,the number of beats produced if the two pipes are vibrating in their fundamental modes simultaneously is:

For a particular resonance tube,following are four of the six harmonics below $1000 \,Hz$: $300, 600, 750$ and $900 \,Hz$. The two missing harmonics are: