Physics - Sound Wave Question with Solution | TestHub

Given wave equation :

$\text{y}={\text{10}}^{-6}\text{sin}\left(\text{100}\mathrm{t}+\text{20x}+\frac{\mathrm{\pi }}{4}\right) \mathrm{m}$

Standard equation : $\text{y}=\text{a sin }\left(\mathrm{\omega t}+\mathrm{k}\text{x}+\mathrm{\varphi }\right)$

Comparing the two, we obtain

$\therefore$$\mathrm{\omega }=100$ and  $\mathrm{k}=20$

$\therefore$   $\frac{\mathrm{\omega }}{\mathrm{k}}=\frac{\text{100}}{\text{20}}$

$\Rightarrow \frac{2\mathrm{\pi n}}{2\mathrm{\pi }/\mathrm{\lambda }}=\mathrm{n\lambda }=\mathrm{v}=5$

$\therefore$  $\mathrm{v}=5 \mathrm{m} {\mathrm{s}}^{-1}$