A physics professor was driving a Maruti car which has its rear wind screen inclined at `theta = 37^(@)` to the horizontal. Suddenly it started raining with rain drops falling vertically. After some time the rain stopped and the professor found that the rear wind shield was absolutely dry. He knew that, during the period it was raining, his car was moving at a constant speed of `V_(c) = 20 km//hr. [tan 37^(@) = 0.75]`
(a) The professor calculated the maximum speed of vertically falling raindrops as `V_(max)`. What is value of Vmax that he obtained.
(b) Plot the minimum driving speed of the car vs. angle of rear wind screen with horizontal `(theta)` so as to keep rain off the rear glass. Assume that rain drops fall at constant speed `V_(r)`

Answer

(a) `V_(max) = 12 km//hr` (b) `(##IJA_PHY_V01_C02_E01_033_A01##)`