The nature of waves


  • A wave is a disturbance in a medium.
  • It carries energy from one point to another without transferring matter.
  • There are two main types: Longitudinal and Transverse.
  • Sound waves are an example of longitudinal waves.
  • Typically, sound waves travel at about 340 meters per second in air at room temperature and pressure.

Ways of showing waves

We use three ways of representing the propagation of waves:

  • Dots.
  • Colour maps.
  • Line graphs.

Wavelength-frequency relation

Frequency f, wavelength λ and wave velocity v are mathematically related by:

v = f λ

Point sources and inverse-square law


The energy carried by waves that radiate uniformly in all directions from a point source decay as the inverse of the square of the distance from the point source. This is known as the inverse square law.

Comments are closed.