0Linear Superposition and Interference
The Double-Slit Experiment
Interference in Thin Films
Interferometers
Interference and Diffraction
Diffraction and Spatial Resolution
Diffractive Spectral Dispersion: Gratings
The Principle of Linear Superposition
When two or more waves are present simultaneously at the same place, the resultant disturbance is the sum of the disturbances from the individual waves.
In the chapter 17 context, we were talking about mechanical waves. But the principle holds for electromagnetic waves as well.
A few terms:
Coherent sources of light emit waves that have a constant phase relationship.
Constructive interference occurs when the field vectors have the same condition at the same place at the same time.
Destructive interference occurs when the field vectors are exactly opposite in condition at the same place at the same time.
If two waves from a coherent source travel two different paths to arrive at a common point, their phase relationship at that point depends on the difference in lengths between their paths.
