Question

A bus with a vertical wind shield moves horizontally

at a speed of 40 km/hr, while rain is falling
vertically at a speed of 30 km/hr. The angle at
which rain drops strike the wind shield is
(1) 37°
(2) 45°
(3) 53°
(4) 30°​

Answer 1

(3) 53°

Step-by-step explanation:

We want to measure the angle that the rains form with the vertical wind shield, so we have to measure the angle relative to the vertical. This means that we can write the following equation

`tan \theta = (v_x)/(v_y)`

where

`v_y = 30 km/h` is the speed of the rain, which travels vertically

`v_x = 40 km/h` is the speed of the bus, which travels horizontally

Substituting, we find

`\theta=tan^(-1)((40)/(30))=53^(\circ)`