Two perfectly identical wires are in unison. When the tension in one wire is increased by $1\%$,then on sounding them together $3$ beats are heard in $2 \,s$. The initial frequency of each wire is .... $\text{s}^{-1}$.

Two waves $Y_1 = 0.25 \sin(316t)$ and $Y_2 = 0.25 \sin(310t)$ are propagating along the same direction. The number of beats produced per second is:

$A$ source of unknown frequency gives $4\, \text{beats/s}$ when sounded with a source of known frequency $250\, \text{Hz}.$ The second harmonic of the source of unknown frequency gives $5\, \text{beats/s}$ when sounded with a source of frequency $513\, \text{Hz}.$ The unknown frequency is .... $\text{Hz}$

An observer while going on a scooter hears the sound of two sirens of the same frequency from two opposite directions. If he travels along the direction of one of the sirens,then he:

When a vibrating tuning fork moves towards a wall,why do we hear sound beats?

Two sound waves of wavelengths $99 \ cm$ and $100 \ cm$ produce $10$ beats in a time of $t$ seconds. If the speed of sound in air is $330 \ m \ s^{-1}$,then the value of $t$ in seconds is