Question

A man walking on a horizontal road with a speed of 5m/s observes,the rain falling at an angle of 45° with vertical. When the man runs at 10m/s , the rain drops hit his head vertically. A) Speed of rain as observed by a man standing on ground will be. B) Angle with vertical in which man at rest must hold umbrella to prevent himself from getting wet.

Answer 1

Relative velocity of man with respect to rain =10-velocity of rain
Tan inverse of Vm/Vr