Question

A car traveling at 80km/h on a level road on a raining day. The trucks of the rain drops on a side window make angle 30° with the vertical. Neglecting the wind velocity, determine the velocity of the rain drops.​

Answer 1

Drawing the vector triangle for given conditions

tan 30 = V / 80

V = 80 km/h * tan 30 = 46 km/h

(Also V = 46 * 1000 / 3600 = 12.8 m/s)

(V = 41.9 ft/s = 41.9 / 88 * 60 = 28.6 mph using 88 ft/sec as 60 mph)