Simple Harmonic Motion definition
The simplest type of harmonic motion i.e. of constant amplitude and single frequency whose acceleration is always directed towards the mean position and is directly proportional to the displacement from the mean position is called simple harmonic motion.
In simple harmonic motion,
Acceleration ἀ displacement
Or, acceleration = – k x displacement
where k is a constant and the negative sign shows that acceleration is directed in opposite direction to the motion of the object.
Examples of simple harmonic motion: motion of simple pendulum, motion of helical spring, etc.
Note:- Motion of the body moving in a uniform circular path is not SHM (Simple Harmonic Motion) rather its projection on any diameter of a circle is SHM (Simple Harmonic Motion).