Question

A man starts running along a straight road with uniform velocity observes that the rain is falling vertically downward. If he doubles his speed, he finds that the rain is coming at an angle `theta` to the vertical. The velocity of rain with respect to the ground is :
A. `uhati-utanthetahatj`
B. `uhati-(u)/tanthetatheta`
C. `utanthetahati-uhatj`
D. `(u)/(tantheta)hati-uhatj`

Answer 1

Correct Answer - B

`rArr vec(v)_(R//M)=u/(tan theta)-hat(j)`
`:. Vec(v)_(R)=vec(v)_(R//M)+vec(v)_(M)`
`rArr vec(v)_(R)=uhat(i)-u/(tan theta) hat(j)`