How are an electric motor and an electric generator alike?

They both rotate to be useful. An electric motor takes electricity to work. An electric generator make electricity, however it needs another power source to make electricity.  more

their made of similar components. passing an electrical current through a generator will cause it to act like an electric motor, while manually spinning the axle attached to an electric motor will cause it to act like a generator (produce an electrical current) this can be demonstrated by some simple LEGO's, the motor, set of wires, and a light and a battery, attaching the battery to the motor will cause the axle attached to spin, attaching a light to the motor, and spinning the axle will cause the light to become lit.  more