Question

define SHM under what condition is the motion of a pendulum simple harmonic

Answer 1

SHM is a type of vibratory motion in which acceleration of body is directly proportional to its displacement and the acceleration is always directed towards the equilibrium (mean) position.
Conditions for SHM
1. There must be an elastic restoring force acting on the system.
2.The system must have inertia.
3.The acceleration of the system should be directly proportional to its displacement and is always directed to mean position. e.g aa-x.

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