Question

Fill in the blank
The sound of frequency $660Hz$ fall normally on a perfectly reflecting wall. The shortest distance from the wall at which the air particles have the maximum amplitude of vibration is ______ $m$.

Answer 1

Shortest distance, $d=\frac{\lambda }{4}=\frac{v}{4f}=\frac{330}{4\times 600}=0.1375m$