Summary
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.