Question
A person running horizontally observes that rain is falling on his head vertically with speed $10\,m/s$. He stops and observes that rain is coming at an angle $30^o$ with vertical., find the speed with which man was running
✓
Answer
$\mathrm{V}_{\mathrm{m}}=\mathrm{V}_{\mathrm{r}} \sin 30^{\circ}$
$=\frac{20}{\sqrt{3}} \times \frac{1}{2}=\frac{10}{\sqrt{3}} \mathrm{m} / \mathrm{s}$
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