Introduction to waves

What are waves?

Waves are vibrations that transfer energy from one place to another.

No matter (solid, liquid, gas) is transferred, just energy.

Transverse

In transverse waves the particles all move at right angles to the direction of the wave

EXAMPLES:

Light waves
Other electromagnetic waves
Some seismic waves
Sea waves

Longitudinal

In longitudinal waves the particles all move in the same direction as the wave is travelling.

EXAMPLES:
Sound waves
Some seismic waves

Parts of a wave

You will have seen what a wave looks like in the unit about sound.
You should remember that we talked about pitch and loudness when we talked about sound waves.

These actually relate to the amplitude and the wavelength.

High pitch sounds have a short wavelength and low pitch sounds have a long wavelength.

Loud sounds have a bigger amplitude (are taller) than quiet sounds.

Amplitude

The amplitude is the maximum distance of a point on the wave from its rest position (measured in metres).

Frequency

The frequency is the number of waves passing a point each second (measured in hertz).

Wavelength

The wave length is the distance from the point of one wave to the same point on the next wave (measured in metres).