It's Raining!Level pending
The slopes of the wind-screen of two motorcars are α = 30° and β = 15° respectively. The first car is travelling with a velocity of v1 horizontally. The second car is travelling with a velocity v2 in the same direction. The hail stones are falling vertically. Both the drivers observe that the hail stones rebound vertically after elastic collision with the wind-screen. Find the ratio of v1/v2.