This physlet will show the phasor addition of two vectors. You can specify the magnitudes of the vectors, and the phase angle between them. (After changing the numbers, click the Update Phasors button.) The graph on the left shows the rotating Vector A, and Vector B and the net Vector C. The middle graph shows the rotating vector addition diagram. The graph on the right plots the amplitudes of the individual vectors, and the combined vector.
Vector A = Vector B = Phase Angle = degrees
Intensity as a function of phase angle
In the graph to the right,