Two similar open organ pipes of length $50 \, cm$ and $50.5 \, cm$ produce $3$ beats per second when sounded together. The velocity of sound in air is ........ $m/s$.

$A$ 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 (in $cm$)? (Speed of sound in air $= 340 \ m/s$)

If the fundamental frequency of a closed pipe is $50\,Hz$,then the frequency of the $2^{nd}$ overtone is .... $Hz$.

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:

$A$ pipe of length $85\, cm$ is closed from one end. Find the number of possible natural oscillations of the air column in the pipe whose frequencies lie below $1250\, Hz$. The velocity of sound in air is $340\, m/s$.

$A$ tuning fork of frequency $n$ is held near the open end of a tube which is closed at the other end,and the length is adjusted until resonance occurs. The first resonance occurs at length $L_1$ and the immediate next resonance occurs at length $L_2$. The speed of sound in air is