$A$ tuning fork $A$ produces $5$ beats per second with a tuning fork of frequency $480 \ Hz$. When a little wax is stuck to a prong of fork $A$,the number of beats heard per second becomes $2$. What is the frequency of tuning fork $A$ before the wax is stuck to it (in $Hz$)?

Beats are produced by waves $y_1 = a \sin(2000 \pi t)$ and $y_2 = a \sin(2008 \pi t)$. The number of beats heard per second is

Two sitar strings $A$ and $B$ playing the note $Sa$ are slightly out of tune and produce beats of frequency $5 \ Hz$. The tension of the string $B$ is slightly decreased and the beat frequency is found to decrease to $3 \ Hz$. What is the original frequency of $B$,if the frequency of $A$ is $255 \ Hz$?

Two vibrating strings $A$ and $B$ produce beats of frequency $8 \ Hz$. The beat frequency is found to reduce to $4 \ Hz$ if the tension in the string $A$ is slightly reduced. If the original frequency of $A$ is $320 \ Hz$,then the frequency of $B$ is: (in $Hz$)

Ten tuning forks are arranged in increasing order of frequency in such a way that any two consecutive tuning forks produce $4$ beats per second. The highest frequency is twice that of the lowest. Possible highest and lowest frequencies (in $Hz$) are ................

For the formation of beats,two sound notes must have: