This worksheets shows the relationship between a rotating vector and the corresponding sinusoidal waveform. Phasor Diagrams are used in Electrical Engineering to represent the relationship of different AC signals at an instant of time.
Adjust the amplitude of the sinusoidal waveform with the slider. Move the slider "t" to rotate the vector [math]\underline{u}[/math]. Move the tip of the vector [math]\underline{u}(t=0)[/math] to set the starting angle.