When a tuning fork $A$ of unknown frequency is sounded with another tuning fork $B$ of frequency $256 \ Hz$,then $3$ beats per second are observed. After that,$A$ is loaded with wax and sounded again,and $3$ beats per second are observed. The frequency of the tuning fork $A$ is ..... $Hz$.

When two waves of almost equal frequencies $v_1$ and $v_2$ reach a point simultaneously,the time interval between successive maxima is

$A$ vibrating tuning fork of frequency $n$ is placed near the open end of a long cylindrical tube. The tube has a side opening and is fitted with a movable reflecting piston. As the piston is moved through $8.75 \, cm$,the intensity of sound changes from a maximum to a minimum. If the speed of sound is $350 \, m/s$,then $n$ is .... $Hz$.

Two identical wires have a fundamental frequency $f_0$ when kept under the same tension $T$. If the tension of one wire is increased by $\Delta T$,then $N$ beats occur when both wires oscillate simultaneously. Find the expression for $\frac{\Delta T}{T}$.

What should be the frequency of beats so that they can be heard clearly in the case of sound?

Two sound sources,when sounded simultaneously,produce four beats in $0.25 \ s$. The difference in their frequencies must be: (in $Hz$)