Edexcel GCSE Physics key terms

A rigid bar that can turn about a pivot to transmit the turning effect of an applied force.

A light-sensitive resistor whose resistance decreases as the intensity of the light falling on it increases.

A device that detects when an interrupt card passes through a light beam, allowing time and velocity to be measured without human reaction-time delay.

The amount of light reaching a given area; greater light intensity means brighter illumination at the LDR.

A large electrostatic spark caused by a build-up of charge in storm clouds and a sudden transfer of charge.

Charges of the same type: either both positive or both negative.

The point beyond which force and extension are no longer directly proportional.

A distortion in which extension is directly proportional to the applied force.

A relationship represented by a straight line on a graph; equal changes in one variable produce equal changes in the other.

The straight line along which a force acts, extended if necessary.

The pressure produced by the weight of the liquid above a point.

The mains wire whose potential alternates relative to the neutral and earth wires; its working potential difference from either is about 230 V.

A wave whose oscillations are parallel to its direction of travel.

A substance such as oil or grease placed between moving surfaces to reduce friction.

The use of a substance such as oil or grease between moving surfaces to reduce friction.

A small region within a ferromagnetic material in which many atomic magnetic effects are aligned in the same direction.

A region in which a magnet, magnetic material or current-carrying conductor experiences a magnetic force.

An imaginary line used to represent a magnetic field; its direction is the direction in which a north magnetic pole would move.

A measure of how strong a magnetic field is at a particular point.

A measure of the strength of a magnetic field, represented by $B$ and measured in tesla (T), equivalent to newtons per ampere metre (N/A m).

A push or pull arising from an interaction between magnetic fields.

The process by which a magnetic material becomes magnetised while it is in a magnetic field.

Either end of a magnet, where its magnetic field is strongest; the two types are north and south.

Describes an image that is larger than its object.

The size of a quantity without reference to its direction or sign.

The long, stable stage during which a star fuses hydrogen into helium in its core.

A stable star in which energy released by nuclear fusion provides an outward effect that balances gravitational contraction.