Question

According to the principle of conservation of mechanical energy :
(a) Potential energy of a system is always greater than its kinetic energy
(b) Kinetic energy of a system is always greater than its potential energy
(c) Mechanical energy is always converted into heat energy
(d) Total mechanical energy of a system remains constant if no external force is worked on it.

April 24, 2024

Answer

(d) Total mechanical energy of a system remains constant if no external force is worked on it.

Reason — The conservation of mechanical energy states that the total mechanical energy (sum of kinetic energy and potential energy) of a system remains constant if no external forces, such as friction or air resistance, are acting on it.

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