Edexcel GCSE Combined Science key terms

Water in its gaseous state.

The unit of power. One watt is a transfer rate of one joule per second: $1\text{ W}=1\text{ J/s}$.

A disturbance that transfers energy and information without a net transfer of matter.

A line joining points on a wave that are at the same stage of their vibration, such as a line along a wave crest.

The distance between corresponding points on consecutive waves, such as two adjacent crests, measured in metres.

The distance travelled by a wave per second, measured in metres per second (m/s).

The speed of a travelling wave together with its direction of travel. Wave speed is measured in metres per second (m/s).

An acid that only partially dissociates into ions in aqueous solution.

The force acting on an object due to gravitational attraction, measured in newtons (N).

The transfer of energy by a force moving an object through a distance in the direction of that force; measured in joules (J).

Plant transport tissue containing hollow, lignified dead cells that carry water and dissolved mineral ions from roots towards leaves.

The diploid cell formed when two haploid gametes fuse at fertilisation.