Question
Sun July 29, 2012 By:

A man standing on a road has to hold his umbrella at 30 degrees with the vertical to keep the rain away.He throws the umbrella and starts running at 10 km/h.He finds that raindrops are hitting his head vertically.Find the speed of the raindrops with respect to (i)the road (ii)the moving man

Expert Reply
Sun August 05, 2012
Angle of rain, a = 30 degrees
 
when the man runs with the speed of 10 km/h he finds that rain falls verically that means that the horizontal component of rain was 10 km/h.
Vx = 10 km/h
thus now vertical comppnent of rain is, Vy:
 
Vx/Vy = tan 30
 
Vy = 17.32 km/h
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