Two identical stringed instruments have a frequency of $100 \ Hz$. If the tension in one of them is increased by $4\%$ and they are sounded together,then the number of beats produced in one second is:

Two tuning forks of frequencies $256 \ Hz$ and $258 \ Hz$ are sounded together. The time interval between two consecutive maxima is (in $s$)

Two tuning forks $A$ and $B$ produce notes of frequencies $256 \ Hz$ and $262 \ Hz$ respectively. An unknown note sounded at the same time as $A$ produces beats. When the same note is sounded with $B$,the beat frequency is twice as large. The unknown frequency could be ... $Hz$

Each of the two strings of length $51.6 \, cm$ and $49.1 \, cm$ are tensioned separately by $20 \, N$ force. The mass per unit length of both strings is the same and equal to $1 \, g/m$. When both strings vibrate simultaneously,the number of beats is:

$A$ set of $24$ tuning forks is arranged in a series of increasing frequencies. If each fork gives $4 \, Hz$ beats per second with the preceding one and the frequency of the last tuning fork is two times that of the first fork,find the frequency of the $5^{th}$ tuning fork in $Hz$.

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