Waves
Progressive Waves
Progressive waves are waves which transfer energy. There are two main types of progressive waves: longitudinal and transverse. The main differences between these two types of waves is longitudinal vibrate in the same direction as the wave direction, however transverse waves vibrate at 90 degrees to the wave direction
Sound waves are an example of longitudinal waves. Sound is also a mechanical wave, it requires a medium in order to travel. Light is an example of a transverse wave, it is an example of electromagnetic radiation and therefore it does not require a medium in order to travel.
Features of waves
Frequency
The number of vibrations per second in Hertz
Period
The time for one vibration in seconds
Displacement
The distance moved by a particle from its disturbance position
Wave speed
Speed at which energy is transferred
Wave equilibrium
No particle displacement
Amplitude
The maximum displacement of a point from equilibrium
Rarefaction
Point where the particles in a longitudinal wave are at maximum separation
Compression
Point where the particles in a longitudinal wave are at minimum separation
Wavelength
Shortest distance between two vibrations in phase
