Electromagnetic Induction (EdExcel)

Potential Difference

The energy transferred per unit charge as it moves between two points in an electric circuit, measured in volts (V).

Formula for Potential Difference (V)

V = W/Q, where V is potential difference (volts), W is work done (joules), and Q is charge (coulombs).

Ohm's Law

Describes the relationship between potential difference (V), current (I), and resistance (R) as V = I * R.

Electromagnetic Induction

The process of generating a potential difference in a conductor by moving it through a magnetic field.

Alternating Current (AC) Generator

A device that produces a potential difference by converting mechanical energy into electrical energy, creating an alternating current.

Dynamo

A direct current (DC) generator that produces a potential difference using a split ring commutator.

Motor Effect

The principle where a current interacting with a magnetic field causes movement, as seen in loudspeakers and headphones.

Induced Current

The current caused by a potential difference that results from electromagnetic induction.

Generator Effect

The process by which a changing magnetic field induces a potential difference and current in a coil.

Sine Curve in Alternators

The output of an alternator represented on a voltage-time graph, showing alternating voltage.

Factors Affecting Induced Potential

The induced potential difference increases with faster speed of movement, stronger magnetic field strength, and more turns in the coil.