A progressive wave is
A wave that transfers energy from one point to another without transferring the medium itself
Properties of a progressive wave
Displacement
Amplitude
Wavelength
Time period
Frequency
Speed
Wave equations
f=1/T
λ = v/f
Phase difference definition
The phase difference between two waves is a measure of how much a point or a wave is in front or behind another
Phase difference
Phase difference is measured in fractions of a wavelength, degrees or radians
The phase difference can be calculated from two different points on the same wave or the same point on two different waves
The phase difference between two points can be described as:
In phase is 360° or 2π radians
In anti-phase is 180° or π radians