The sound waves of wavelengths $5 \,m$ and $6 \,m$ produce $30$ beats in $3 \,s$. The velocity of sound is (in $\,m/s$)

Two identical piano wires,kept under the same tension $T$,have a fundamental frequency of $600\, Hz$. The fractional increase in the tension of one of the wires which will lead to the occurrence of $6\, beats/s$ when both the wires oscillate together would be:

Each of the two strings of length $51.6 \, cm$ and $49.1 \, cm$ are tensioned separately by $20 \, N$ force. The mass per unit length of both strings is the same and equal to $1 \, g/m$. When both strings vibrate simultaneously,the number of beats is:

$41$ tuning forks are arranged in such a way that each produces $5 \text{ beats per second}$ when sounded with its nearest fork. If the frequency of the last fork is double the frequency of the first fork,then the frequencies of the first and last fork are respectively:

Two tuning forks of frequencies $320 \ Hz$ and $323 \ Hz$ are vibrated together. The time interval between a maximum sound and its adjacent minimum sound heard by an observer is

Beats are produced by two waves given by $y_{1} = a \sin(2000 \pi t)$ and $y_{2} = a \sin(2008 \pi t)$. The number of beats heard per second is