Simple Harmonic Motion & Phase 

This applet shows a number of particles in Simple Harmonic Motion. All the particles have
the same amplitude and frequency but are at different positions at any given moment. Phase expresses this difference. Each of the particles
in motion can be associated with a particle on the circle. Phase is then the angular position
of the particle on the circle. Phase increases continuously
with time, going up by 2π radians for every oscillation. Since all
the particles shown in the applet have the same frequency, the phase increases at the same
rate for all of them and so the phase difference between them does not change with time. Phase
is one variable which can be related to all other variables easily (position, velocity,
and acceleration). This means that knowing the constants of a SHM and the phase would be
enough to completely define it. 
Applet Menu 