A smooth square platform ABCD is moving towards right with a uniform speed v. At what angle `theta` must a particle be projected from A with speed u so that it strikes the point B

Options

A. `sin^(-1)(u/v)`
B. `cos^(-1)(v/u)`
C. `cos^(-1)(u/v)`
D. `sin^(-1)(v/u)`

Answer

b

Explanation

Particle will strike the point B if velocity of particle with respect to platform is along AB or component of its relative along AD is zero.
So, `u cos theta=v`
or `theta=cos^(-1)(v/u)`