A particle of mass 1 kg is projected at an angle of `theta = pi/4` from horizontal with a muzzle velocity of 20 m/s. A long slender rod of mass 5 kg and length 30m is suspended vertically from a point at the same horizontal level as that of projection and at a distance of 60 m from the projection point.The rod can rotate freely. If collision occurs, it is perfectly inelastic. `(g =10m//s^2)`

The particle will

Options

A. not hit the rod at all
B. hit the rod at A
C. hit the rod between O and A, not at its mid point
D. hit the rod at its mid point

Answer

B

Explanation

`t = (S_x)/(U_x) = 60/(10sqrt(2)) = 3sqrt(2)s`
`S_y = 20/(sqrt2) xx 3sqrt(2) - 1/2 xx 10(3sqrt(2))^2 = 60 - 90 = -30 m` ie., the particle will hit the rod at A.