Question

Effect on phase and epoch in simple harmonic motion

Answer 1

Epoch is the initial phase of a particle and it remains constant all the time for a given motion. ... Frequency is defined as the number of periodic motions executed by a body per second.

Displacement in SHM is given by x = A sin( wt) where A is amplitude, w is angular velocity, t is instantaneous time. Phase difference between sin and cos function is 90 degrees or pi/2 radians . Hence phase difference between displacement and velocity is 90 degrees or pi/2 radians.