Question

The distance between two consecutive points with phase difference of $60^{\circ}$ in a wave of frequency $500 \,Hz$ is $6.0\, m$. The velocity with which wave is traveling is ___$km / s$

Answer 1

$\Delta \phi=\frac{2 \pi}{\lambda} \Delta x$
$ \frac{\pi}{3}=\frac{2 \pi}{\lambda}(6 m )$
$ \Rightarrow \lambda=36 \,m $
$ V = f \lambda=(500 \,Hz )(36\, m )$
$ =18000 \,m / s =18 \,km / s $