On an incliend plane two particles A and B are projected with same speed at the same angle with the horizontal, particle A down and particle B up the plane. If the ratio of time of flight of A and B is cot `theta`, is the angle at which B is projected measured from. inclined plane, find the angle at which particles are projected.

Options

A. `90^(@)`
B. `60^(@)`
C. `30^(@)`
D. `45^(@)`

Answer

d

Explanation

Let B makes an angle `alpha` with horizontal.
So `gamma+alpha=theta`