DC motor

Interactions

drag the coil or the flywheel: turn the rotor by hand or hold it stalled; the current climbs and the brushes glow
click the battery: the two leads are swapped, the motor slows through zero and runs the other way
click the weights: one more slotted disc goes on the hanger (when none are left, they all come off); the motor slows and draws more current
click the magnet: a soft-iron plate is laid across its arms, the field weakens and the light motor speeds up