OCR GCSE Physics A key terms

An increase in the wavelength of light received from an object moving away from us.

An increase in the observed wavelength of light from a receding object, accompanied by a decrease in its frequency.

The ray that travels away from a surface after reflection.

The return of electromagnetic radiation from a surface or boundary into the original medium.

The ray that travels through the second substance after crossing a boundary.

A change in direction of a wave as it passes from one substance into another.

A source of energy that is replenished naturally as it is used, such as wind or sunlight.

An energy resource that is naturally replenished at least as quickly as it is used, or remains available for the foreseeable future.

A measure of how strongly a component opposes the flow of electric charge, measured in ohms (Ω).

The smallest change in a quantity that a measuring instrument can show.

The process of replacing one force with perpendicular components that together have the same effect.

The action produced after a stimulus has been detected, such as closing the fingers or pressing a key.

The single force that has the same effect as all the forces acting on an object combined. It is related to acceleration by $F = ma$.

The overall turning effect of all the forces acting on an object.

A change that can be undone so that the original material and its properties are recovered.

A rule for finding the magnetic-field direction around a current-carrying wire: point the right thumb along the conventional current and the curled fingers show the field direction.

Movement of an object around a fixed point or axis.

An object that orbits a planet or another larger body.

A quantity that has magnitude but no direction.

A quantity that has magnitude but no direction.

The redirection of light in many directions, for example by a rough surface or within a translucent material.

A simplified representation used to explain observations and make predictions.

The coil of a transformer across which the output potential difference is produced.

The potential difference across the output coil of a transformer.

A connection in which components lie one after another on a single path for current.

An electrical arrangement with one complete path from one terminal of a cell or battery to the other.

An unintended route with very low resistance that can produce a dangerously large current.