When two sound sources of the same amplitude but of slightly different frequencies $v_1$ and $v_2$ are sounded simultaneously,the sound one hears has a frequency equal to

Two harmonic waves moving in the same direction superimpose to form a wave $x = a \cos(1.5 t) \cos(50.5 t)$ where $t$ is in seconds. Find the period with which they beat (close to the nearest integer). (in $s$)

Beats are the result of

Two wires are producing fundamental notes of the same frequency. Change in which of the following factors of one wire will not produce beats between them?

Draw graphs of beats produced by two harmonic waves of frequency $11 \ Hz$ and $9 \ Hz$.

$25$ tuning forks are arranged in series in the order of decreasing frequency. Any two successive forks produce $3 \, Hz$ beats. If the frequency of the first tuning fork is the octave of the last fork,then the frequency of the $21^{st}$ fork is .... $Hz$