Question

what is difference between a compression and rarefaction in a sound wave
​

Answer 1

A compression is a region in a longitudinal wave where molecules are close together . A rarefaction is a region in a longitudinal wave where molecules are further apart from one another

Answer 2

Compression. A portion of the medium where a temporary reduction in volume and consequently an increase in density and pressure takes place when a sound Wave passes through the medium is called a compression or a condensation.

Rarefaction.A portion of the medium where a temporary increase in volume and consequently a decrease in density takes place when a sound Wave passes through the medium is called a rare faction.