Coupled Pendulum Simulation
Couple two identical pendulums and energy sloshes from one to the other and back. This simulation shows that exchange, and lets you find the two special modes in which it does not happen at all.
How to use this simulation
- Set the initial displacement of each pendulum
- Change the coupling strength
- Start the system in either pure normal mode
What to look for
- Energy transfers completely from one pendulum to the other, then back
- Starting in a pure normal mode gives steady motion with no transfer
- Stronger coupling speeds up the exchange
The physics behind it
A coupled system has normal modes: in-phase, where both swing together at a lower frequency, and antiphase, where they oppose each other at a higher one. Starting one pendulum alone excites both modes equally, and their slightly different frequencies beat against each other, transferring all the energy across and back at the beat frequency.