Question

A glass wind screen whose inclination with the vertical can be changed is mounted on a car. The car moves horizontally with a speed of 2m/s. At what angle α with the

A glass wind screen whose inclination with the vertical can be changed is mounted on a car. The car moves horizontally with a speed of ( 2 mathrm{m} / mathrm{s} ). At what angle ( alpha ) with the vertical should the wind screen be placed so that the rain drops falling vertically downwards with velocity ( 6 mathrm{m} / mathrm{s} ) strike the wind screen perpendicularly?

JEE/Engineering Exams

Physics

Solution

4.0 (1 ratings)

Velocity of rain with respect to car should be perpendicular to the screen.
relative velocity( =overrightarrow{v_{text {rain}}}-overrightarrow{v_{text {car}}} )
( tan alpha=frac{V_{r}}{V_{c}}=frac{6}{2}=3 )
( alpha=tan ^{-1} 3 )