G1-58
Analog to the longitudinal motion of a particle in a particle accelerator driven by a sinusoidal accelerating potential.
The position of the pendulum bob, displaced from the vertical by the hanging weights, represents the phase of a particle being accelerated in a particle accelerator. The sinusoidal accelerating voltage creates oscillations of the particle about its equilibrium phase. The phase of the accelerating particle oscillates about the equilibrium phase, as does the pendulum.