OCR GCSE Physics A key terms

A potential difference whose polarity remains in one direction, even if its magnitude changes.

Fluid moved out of the space occupied by an immersed object.

The straight-line change in position from the starting point, including direction; it is a vector quantity measured in metres (m).

Energy transferred to less useful stores and spread into the surroundings rather than destroyed.

The total length of the path travelled by an object, regardless of direction.

The distance moved in the direction in which a force acts.

A graph showing how the total distance travelled changes with time.

The total length of the route followed by an object; it is a scalar quantity and cannot be negative.

The liquid collected after vapour has condensed during distillation.

The electricity supply delivered to buildings through the National Grid and accessed through mains sockets.

A resistive force on an object moving relative to a fluid such as air or water; it acts against the relative motion.

A microphone in which sound moves a coil through a magnetic field, inducing an electrical signal.

A generator that produces direct current by converting mechanical energy into electrical energy.

A flexible membrane in the ear that vibrates when sound waves reach it.

The region around Earth where a magnetic object experiences a magnetic force. Its direction and strength vary with location.

A protective mains wire that connects exposed metal parts of an appliance to earth, where fitted.

A reflected sound wave heard after the original sound.

The fraction of the input energy transfer that is transferred usefully.

A reversible deformation: the object returns to its original shape and dimensions when the forces causing the deformation are removed.

The greatest load for which an object still returns to its original dimensions when the load is removed.

Energy stored when an elastic object is reversibly stretched or compressed.

The energy store of an object that has been stretched or compressed and can return towards its original shape.

A device designed to transfer energy from an electrical supply to other energy stores.

A material that resists the flow of electric current; covering a conductor with it helps prevent accidental contact.

Having zero net charge because the total positive charge equals the total negative charge.

The rate at which energy is transferred, measured in watts (W).

The pathway by which energy is transferred when charges move through a circuit.