Physics key terms

To give out energy as radiation.

Radiation given out by a body, transferring energy away from it.

The region bounded by the plotted line, the time axis and the relevant start and finish times.

The capacity of a system to bring about change; energy is stored and transferred, and is measured in joules (J).

The transfer of energy from electrical cables to the surroundings by heating.

The amount of energy used per unit of activity or output; a decrease usually indicates improved energy efficiency.

One of the different energies an electron can have in an atom; electrons at higher energy levels are further from the nucleus in this model.

A source of energy that people can use for heating, transport or generating electricity.

A way in which energy is held, such as a kinetic, thermal, chemical or gravitational potential energy store.

The movement of energy from one store to another, either within a system or across its boundary.

A representation using boxes and arrows to show how energy moves between stores.

A mechanism by which energy moves between stores, such as mechanical work, electrical work, heating or radiation.

Energy moved from one store to another or carried from one place to another, measured in joules (J).

Total energy use divided by the number of people; an average, not the amount used by every individual.

A change to the surroundings caused by an activity, such as pollution or habitat loss from energy use.

A state in which the forces on an object are balanced, so the resultant force is zero.

The undisturbed position about which a particle or object oscillates.

One resistor that could replace a combination of resistors while producing the same total resistance.

A mark on a graph showing the uncertainty or spread associated with a plotted value.

A value close enough for the intended purpose, usually found using suitable assumptions and rounded data.

A question about what people ought to do, involving judgements about values, rights or responsibilities.

An overflow vessel with a spout used to collect liquid displaced by an immersed object.

The change from a liquid to a gas at its surface.

Information obtained through observations or investigations and used to assess a scientific claim or explanation.

A change to a higher energy level after energy has been absorbed.

A nucleus left with excess energy, often following another radioactive decay.

A temporary higher-energy condition of an atom after one of its electrons has absorbed energy and moved to a higher energy level.