A train is travelling along a horizontal rail at the rate of `90km//hr` and rain, driven by wind blowing in the direction of motion of trani, falls at a velocity of `12.5m//s` making an angle of `30^(@)` to the vertical. Find the velocity of rain (in magnitude and direction) as seen from the train.

Options

A. `(25sqrt(2))/2 m//s`, inclined at an angle of `30^(@)` to the vertical away from train's motion.
B. `(25sqrt(3))/2 m//s`, inclined at an angle of `30^(@)` to the vertical away from train's motion.
C. `(35sqrt(2))/2 m//s`, inclined at an angle of `60^(@)` to the vertical away from train's motion.
D. `(25sqrt(3))/2 m//s`, inclined at an angle of `60^(@)` to the vertical away from train's motion.

Answer

d

Explanation

`v_(t)=9km//h=25m//s`

`x=sqrt(25^(2)+(12.5)^(2)-2xx25xx12.5 cos 60^(@))`
`=12.5sqrt(4+1-2)=25(sqrt(3))/2`
Now `theta=60^(@)`