Hand cranked induction generator

In the hand cranked induction generator, a coiled wire was attached to a crank that was surrounded my magnets. When a person cranked the generator, they altered the angle of the coiled wire thus inducing a voltage. In an inductor, a change in current (in this case by altering the the current and thus the magnitude of the magnetic field) induces a "back" voltage to halt the change in current. The inductor always wants to be in a state of equilibrium and it does so by creating a "back" voltage. The induced current created by the "back" voltage powers the light bulb.