Question

A loaded spring gun of mass 'M' fires a bullet of mass 'm' with a velocity 'v' at an angle of elevation θ. The gun is initially at rest on a horizontal frictionless surface. After firing, the centre of mass of the gun­–bullet system

• A. Moves with a velocity v m/M
• B. moves with velocity vm/M cos $\theta$ in the horizontal direction
• C. Remains at rest
• D. moves with a velocity $\frac{v(M-m)}{(M+m)}$ in the horizontal direction.

Answer 1

The correct option is C Remains at rest

Since the forces acting during the firing are internal forceson the gun-shot system, the centre of mass of the system continues to remain at rest. Hence the correct choice is (c).