Two particles A and B are projected simultaneously in the direction shown in the figure with velocities `V_(A)=20m//s` and `V_(B)=10m//s` respectively. If they collide in air after 1/2 sec. then

Options

A. the angle `theta` is `60^(@)`
B. the distance x is `5sqrt(3)m`
C. the angle `theta` is `30^(@)`
D. The distance x is `15sqrt(3)m`

Explanation

Relative velocity of B w.r.t. A along verticaldirection should be zero
`20 sin theta=10, rArr sin theta=1//2`,
`x=20 cos 30^(@)xx(1)/(2)=5sqrt(3)m`