Caused by a periodic disturbance which results in a vibration
Progressive waves
Transport energy from one place to another by causing vibrations in the material or medium through which it moves
Transverse waves
The vibrations of the particles in the medium are perpendicular to the direction in which the wave travels
Longitudinal waves
The vibrations of the particles in the medium are parallel to the direction in which the wave travels
Period (T)
The time taken for one complete vibration
Frequency (f)
The number of complete waves that pass a point in a second
Amplitude (A)
The maximum displacement of a particle from its rest position
Wavelength (λ)
The distance the wave travels in the periodic time, T
In Phase
Two waves are said to be in phase if the particles in the waves are vibrating so at the same instant they are at the same displacement (distance and direction) from their equilibrium positions
Out of Phase
Two waves are said to be out of phase if the particles in the waves are vibrating so at the same instant they are at different displacements (distances and directions) from their equilibrium positions
Phase difference
The time interval or phase angle by which one wave leads or lags another
Unpolarised wave
A wave which is vibrating in more than one plane
Polarised wave
A wave where all the vibrations are confined to one plane
