Two tuning forks $A$ and $B$ are sounded together and produce $4$ beats per second. The frequency of tuning fork $A$ is $320 \,Hz$. When tuning fork $B$ is loaded with wax,the number of beats per second remains $4$. What is the frequency of tuning fork $B$ in $Hz$?

$A$ tuning fork of known frequency $256\,Hz$ produces $5$ beats per second with the vibrating string of a guitar. The beat frequency decreases to $2$ beats per second when the tension in the guitar string is slightly increased. The frequency of the guitar string before increasing the tension was ..... $Hz$.

$A$ pair of tuning forks produces $2$ beats in a time interval of $0.4 \ s$. The beat frequency is .... $Hz$.

Two tuning forks,$A$ and $B$,produce $4$ beats per second when sounded together. The frequency of $A$ is $320 \ Hz$. When some wax is added to $B$ and it is sounded with $A$,$4$ beats per second are again heard. The frequency of $B$ is .... $Hz$.

$A$ tuning fork vibrates with $2$ beats in $0.04$ seconds. The frequency of the fork is .... $Hz$.

$A$ tuning fork $A$ of frequency $250 \,Hz$ and another tuning fork $B$ of frequency $x$ produce $5$ beats per second when vibrated together. If the fork $B$ is waxed and vibrated together with $A$, then $3$ beats per second are produced. Then $x=$ (in $\,Hz$)