Question

If a cannon shell explodes in mid air, then identify the incorrect statements.

• A. The momentum of the system is conserved at the time of explosion.
• B. The kinetic energy of the system always increases.
• C. The trajectroy of centre of mass remains unchanged.
• D. None of the above.

Answer 1

The correct option is B The kinetic energy of the system always increases.

The momentum of the system in the horizontal direction is conserved since there is no external force in the horizontal direction.
The center of mass of the system before and after explosion will have the same trajectory.
We cannot say if the kinetic energy of the system always increases.