Waves transfer energy from one place to another.
There are two categories of waves, longitudinal & transverse waves.
Longitudinal Waves – the oscillations are parallel to the direction of energy transfer. For example sound waves. Longitudinal waves like sound form compressions (areas of high pressure) and rarefaction (areas of low pressure).
Transverse Waves – the oscillations are perpendicular ( at 90o to the direction of energy transfer. For example all electromagnetic waves; Radio, Microwave, Infra Red, Visible Light, Ultra Violet, x-rays and gamma rays. All electromagnetic waves travel at the same speed in a vacuum, 300 000 000 m/s.
Mechanical Waves like water waves, waves on spring, waves on a rope, shock waves can be either longitudinal or transverse.
Waves can be ;
Reflected
Refracted
Diffracted
To describe a wave we would nee to know its;
Wavelength (l) – is measured in metres (m).
Amplitude – is measured in metres (m).
Frequency (f) – is measured in hertz (Hz).
Wave equation
wave speed = frequency x wavelength
(metres per second, m/s) (hertz, Hz) ( metres, m)