Question

define the terms phase epoch and phase difference.

Answer 1

Define the terms phase epoch and phase difference

Answer 2

Phase Epoch

The initial phase of oscillating particle is known as epoch. Its unit is radian

Let a particle oscillating in simple harmonic motion

so trajectory motion ,  y = Asin(ωt ± Ф )

where Ф is epoch

Phase Difference

The difference between two simultaneous varying quantities that have the same frequency measured either as an angle or time.