3D Dynamo: AC and DC Simulation

A dynamo turns motion into electricity: a coil spins in a magnetic field, the flux through it changes, and an EMF ε = NBAω sin ωt is induced. This 3D simulation lets you switch the way the coil is connected to the outside circuit. With slip rings, each end of the coil stays on its own brush, so the output follows the coil's EMF and reverses every half turn: alternating current.

With a split-ring commutator the coil's two ends swap brushes every half turn — exactly when the EMF passes through zero — so every negative half-cycle is flipped up. The output keeps one direction: pulsating DC with the same peak and an average of 2ε₀/π. The graph shows the coil's EMF and the terminal output together so the difference is plain.