Transverse and longitudinal waves explained

Key ideas

1. Waves transfer energy from one place to another, not matter.

2. In a transverse wave the oscillations are at right angles to the direction of energy transfer, like ripples on water.

3. In a longitudinal wave the oscillations are parallel to the direction of energy transfer, like sound in air.

4. Longitudinal waves have compressions (squashed together) and rarefactions (spread out).