Question

A a body is released from a height. During its motion in striking the ground, the quantity which does not change is:
(a) momentum
(b) kinetic energy
(c) potential energy
(d) mechanical energy

April 24, 2024

Answer

(d) mechanical energy

Reason — Mechanical energy, which is the sum of kinetic and potential energy, remains constant during the motion of the body. Initially, when the body is released from a height, it has potential energy. As it falls, this potential energy decreases while its kinetic energy increases. However, the sum of kinetic and potential energy (mechanical energy) remains constant in the absence of external forces like air resistance.

💡 Some Related Questions

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