Question

When two waves of almost equal frequencies `n_(1)` and`n_(2)` reach at a point simultaneously, what is the time interval between successive maxima ?

Answer 1

Let, `" " n_(1)gtn_(2)`
Beat frequency `" " v_(b)=n_(1)-n_(2)`
`:." "` Time period of beats `=T_(b)=(1)/(v_(b))=(1)/(n _(1)-n_(2))`