Electromagnetism

Using a simple motor as a generator.

If a simple motor is turned to produce electricity,
the split - ring commutator will change the current direction every half turn.
Instead of generating alternating current (previous page)
the current is kept positive giving the output shown below.

Current from a Motor used as a Generator

Compare this with the output shown for direct current
and you will see that the two are different.
Direct current from a cell shows a smooth unchanging output.
The output shown above is similar to direct current
because the current only flows in one direction.
It is similar to alternating current because
the current rises from zero to maximum and back again.

This type of output can be made more like ordinary direct current
by using a capacitor to "smooth out the humps".