Question

raindrops are falling vertically with a speed of 5m/s w.r.t ground. To a boy running in rain, rain drops are falling with 10m/s.The speed of the boy and the angle with vertically with which rain is being appeared to the boy will be

Answer 1

v² + 5² = 10²
v = 5√3 m/sec. = speed of the boy.
The velocity of rain and the boy are perpendicular vectors.

Angle with the horizontal = Ф
    Tan Ф = 5 / 5√3  = 1/√3

The boy has to look at 17.32 degrees upwards.