Transverse and Longitudinal Waves

Transverse Waves

Transverse waves vibrate in a direction perpendicular to the direction of propagation of the wave.
Examples of transverse waves include: light waves, waves in a slinky when shaken up and down, and waves on a water surface.
The highest point of a transverse wave is called the crest and the lowest point is called the trough.
The wavelength is the distance between two consecutive crests or troughs.
The amplitude is the maximum displacement from the equilibrium (rest) position.

Longitudinal Waves

Longitudinal waves vibrate in the same direction as the wave is travelling - parallel to the direction of propagation.
Examples of longitudinal waves include: sound waves in air and waves in a slinky when it is stretched out and compressed along its length.
In longitudinal waves, there are regions of compression, where the particles are close together, and regions of rarefaction, where particles are spread apart.
The wavelength in a longitudinal wave is the distance between two consecutive compressions or rarefactions.
As with transverse waves, the amplitude is the maximum displacement from the equilibrium position.

Similarities and Differences

Both transverse and longitudinal waves contain wavelengths, frequencies, amplitudes, and speeds.
Polarisation can only occur with transverse waves. It involves restricting the orientation of the vibrations of the wave.
Sound, a longitudinal wave, can travel through solids, liquids, and gases while light, a transverse wave, can travel through a vacuum.

With a solid understanding of these key points, one would have a strong foundation on the basics of longitudinal and transverse waves.