Question

Two waves each of loudness $L$ superimpose to produce beats. The maximum loudness of the beats will be

• A. $4L$
• B. $L$
• C. $2L$
• D. $noneofthese$

Answer 1

The correct option is A $4L$

$L$ is directly proportional to $A^2$,

on superposition amplitudes add Resultant amplitude is $A+A=2A.$

Hence, resultant loudness is $=4A^2,$

$weknowthat{A}^2\propto L$

$\therefore L_{max}=4L$