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

$A$ tuning fork $A$ of frequency $200 \ Hz$ is sounded with fork $B,$ the number of beats per second is $5.$ By putting some wax on $A,$ the number of beats increases to $8.$ The frequency of fork $B$ is .... $Hz$

The wavelength of one wave is $99 \ cm$ and that of another is $100 \ cm$. If the speed of sound is $396 \ m/s$,the number of beats heard per second is:

What is beat frequency?

When a guitar string is sounded with a $440\, Hz$ tuning fork,a beat frequency of $5\, Hz$ is heard. If the experiment is repeated with a tuning fork of $437\, Hz$,the beat frequency is $8\, Hz$. The string frequency $(Hz)$ is

$A$ tuning fork of unknown frequency produces $4$ beats per second when sounded with another tuning fork of frequency $254 \,Hz$. It gives the same number of beats per second when the unknown tuning fork is loaded with wax. The unknown frequency before loading with wax is ..........