Raindrops are falling vertically at a speed of 120 km/h through air that is moving horizontally at a speed of 40 km/h(i.e. the wind is 40 km/h). At what angle do the drops strike the ground?

1 Answer
Oct 3, 2017

18^@ from vertical or 72^@ from horizontally.

Explanation:

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Air is moving horizontally with 40 km/h speed
Horizontal velocity vector of Air is shown in figure.

Velocity Vector of Raindrops is vertically downward .
Let resulting Velocity of Raindrops makes angle theta from the
vertical.
Then angle
tantheta=v_"Horizontal"/v_"vericle"=40/120=1/3

theta=tan^-1(1/3)approx18^@

Hence Raindrops makes angle 18^@ from the vertical or make angle 72^@ from Horizontal.