Edexcel GCSE Physics key terms

The total number of protons and neutrons in a nucleus.

A boundary where one material meets another.

Anything that has mass and occupies space.

The sum of a set of results divided by the number of results.

The average magnitude of the force opposing a vehicle's motion while it is braking.

A process in which a force acts as an object or part of a machine moves through a distance.

Energy transferred when a force moves an object through a distance.

The material through which a wave travels, such as water or air.

The change from a solid to a liquid; energy is transferred to the substance while it changes state.

The SI unit of speed, meaning the number of metres travelled each second.

Electromagnetic radiation between radio waves and infrared in the spectrum, used for communication and for heating food.

A material in a nuclear reactor that slows down neutrons so that they are more likely to cause further fission.

A particle made from two or more atoms chemically bonded together.

The turning effect of a force about a pivot or axis.

The turning effect of a force about a pivot, equal to the force multiplied by its perpendicular distance from the pivot; measured in newton metres (N m).

The product of an object's mass and velocity; it is measured in kilogram metres per second and has a direction.

The force experienced by a current-carrying conductor in a magnetic field.

A unit larger than the unprefixed unit, formed using a multiplier greater than one, such as a kilometre.

A change in the genetic material of a cell.

Meeting or acting at an angle of 90°.

The network of cables and transformers that transfers electricity from power stations to consumers across the country.

A naturally occurring body that orbits a planet, such as the Moon orbiting Earth.

A large cloud of gas and dust from which stars can form.

An overall charge caused by an object having more electrons than protons.

A thermistor for which resistance decreases as temperature increases.

The overall change after all increases and decreases have been combined.

The overall force after all the forces acting have been combined, taking their directions into account.