Two sound waves of wavelengths $\lambda_1$ and $\lambda_2$ $(\lambda_2 > \lambda_1)$ produce $n$ beats per second. The speed of sound is:

The wavelengths of two sound notes in air are $\frac{40}{195} \,m$ and $\frac{40}{193} \,m$. Each note produces $9$ beats per second separately with a third note of fixed frequency. The velocity of sound in air in $m/s$ is

Two waves of lengths $50 \; cm$ and $51 \; cm$ produce $12$ beats per second. The velocity of sound is .... $m/s$.

$A$ tuning fork of frequency $100 \, Hz$ when sounded together with another tuning fork of unknown frequency produces $2$ beats per second. On loading the tuning fork whose frequency is not known and sounding it together with the tuning fork of frequency $100 \, Hz$,it produces one beat. The frequency of the other tuning fork is: (in $, Hz$)

$A$ prong of a vibrating tuning fork is in contact with the water surface. It produces concentric circular waves on the surface of the water. The distance between five consecutive crests is $0.8 \ m$ and the velocity of the wave on the water surface is $56 \ m/s$. The frequency of the tuning fork is: (in $Hz$)

Two tuning forks with frequencies $380 \,Hz$ and $384 \,Hz$ are sounded together. They produce $4$ beats per second. What is the time interval between the maximum sound and the next minimum sound?