Question

Rain is falling vertically with a speed of 30 ms^-1. A woman rides a bicycle with a speed of 10 ms^-1. In the north to south direction. Which is the direction in which she should hold her umbrella?

Answer 1

In order to protect herself from rain, the woman should hold her umbrella in the direction of relative velocity of rain w.r.t., woman vector v_w.

So, the woman should hold her umbrella at an angle of 18º26' with the vertical, towards south.