Question

A large rectangular box ABCD falls vertically with an acceleration ‘a’. A toy gun fixed at ‘A’ and aimed towards C fires a particle P

(a) P will hit C if a=g

(b) P will hit the roof BC if a>g

(c) P will hit the wall CD or the floor AD if a< g

(d) Can’t say

Solution

Super impose an upward acceleration 'a' on the system. The box becomes stationary. The particle has an upward acceleration 'a' and a downward acceleration 'g'.

If a=g, the particle has no acceleration and will hit 'C'.

If a>g, the particle has a net upward acceleration and will hit the roof BC.

If a< g,the particle has net downward acceleration nad will hit the wall CD or the floor AD.

Therefore, options (a),(b) and (c) are correct.