Question

Find the direction for an umbrella when rain falls vertically with speed 20 ms^-1 and wind blows from east to west with a speed of 15 ms^-1.

Answer 1

From the figure

tan \(\theta=\frac{v_w}{v_r}=\frac{15}{20}=\frac{3}{4}\)

tan \(\theta=0.75\)

or \(\theta\approx37^0\)