Each utensil has its own, intricate process of being made: here's how a coil of stainless steel wire turns into a fork. This footage comes from "How It's Made," on the Science Channel, which you ...

In a dynamo, a split ring commutator changes the coil connections every half turn. As the induced potential difference is about to change direction, the connections are reversed. This means that ...

current flows through the wire into the voice coil, which moves the cone and breaks the circuit. The speaker’s diaphragm resets the cone, completing the circuit and repeating the whole process.