Question

To a man in car which is moving due east with a speed of 20 m/s, the rain appears to fall at an angle of 30º with vertical. When he reduces the speed to 8 m/s, again the rain appears to fall at the same angle with vertical. Find the velocity of rain.

Answer 1

Answer:

v

R

=−10

i

^

−10

3

j

^

v"

m

=−v

x

i

^

v

RM

=−(10−v

x

)

i

^

−10

3

j

^

Angle with the vertical = 30

∘

⇒tan30

∘

=

−10

3

10−v+x

⇒v

x

=20m/s

Answer 2

I thought you might understand