Phase Angle

Phase angle refers to the angle between a point on a periodic wave and a reference point. The reference point may be a point on another periodic wave.

The angular measurement that defines the relationship between the periodic wave and the reference point is derived from a projection of a rotating vector onto the real axis of an Argand diagram. The phase angle of a point on a wave is the value of the point on the abscissa that corresponds to the point on the wave. The phase angle of a vector may be written as
M , where M is the magnitude of the vector and is the phase angle relative to the specified reference.