Physics - Wave on String Question with Solution | TestHub

Distance between two consecutive points $60°$ out of phase is given by $\mathrm{\Delta }x=\frac{\lambda }{2\pi }\mathrm{\Delta }\varphi$

Putting the values, we have

$6=\frac{\lambda }{2\pi }\left(\frac{\mathrm{\pi }}{3}\right)$

$\Rightarrow \lambda =36 \mathrm{m}$

Now, velocity of wave is $v=f\lambda =(500 \mathrm{Hz})(36 \mathrm{m})$

$=18000 \mathrm{m} {\mathrm{s}}^{-1}=18 \mathrm{km} {\mathrm{s}}^{-1}$