A generator contains coils of wire that spin in a magnetic field. A potential difference (voltage) is created or induced across the ends of the wire when it cuts across the magnetic field lines. If the wire is part of a complete circuit, the induced p.d. makes an electric current pass round the circuit.
This current can be increased if:
- A stronger magnet is used
- The wire moves faster
The Dynamo Effect:
If you were to connect some insulated wire to an ammeter, and move the wires between the poles of a U-Shaped magnet; You would observe that the ammeter pointer deflects as a current is generated when the wire cuts across the magnetic field. This, is whats known as the Dynamo Effect.