A man moving in rain holds his umbrella inclined to the vertical even though the rain drops are falling vertically downwards. Why?

A man moving in rain holds his umbrella inclined to the vertical even

1.	A man moving in rain holds his umbrella inclined to the vertical even though the rain drops are falling vertically downwards. Why?
Answer» Solution :Let us consider a person moving horizontally with velocity `vec(V)_(m)`. Let rain falls vertically with velocity `vec(V)_(R)`. An umbrella is held to avoid the rain.Then the relative velocity of the rain with RESPECT to the person is , `vec(V) _(RM)= vec(V)_(R)- vec(V)_(M)` Its magnitude is given by `V_(RM) = sqrt(vec(V)_(R)^(2)+vec(V)_(M)^(2))` Its direction is given by `theta = tan^(-1) ((V_(M))/(V_(R)))`With the vertical . In order to SANE himself from the rain, he should hold an umbrella at an angle `theta`with the vertical.