Longitudinal and transverse waves

Waves can be longitudinal or transverse.

Transverse waves

In transverse waves, the oscillations are at right angles to the direction of travel and energy transfer.

Light and other types of electromagnetic radiation are transverse waves. All types of electromagnetic waves travel at the same speed through a vacuum, such as through space.

Water waves and S waves are also transverse waves.

A hand holds a length of rope taut

1. A hand holds a length of rope taut

Longitudinal waves

In longitudinal waves, the oscillations are along the same direction as the direction of travel and energy transfer.

Sound waves and waves in a stretched spring are longitudinal waves. P waves are also longitudinal waves.

Longitudinal waves show areas of compression and rarefaction. In the slideshow below, the areas of compression are where the parts of the spring are close together, while the areas of rarefaction are where they are far apart.

An outstretched slinky spring

1. An outstretched slinky spring