Huygen's Principle
Huygen's Principle
Christiaan Huygens described how to determine the path of waves through a medium.
Definition: The Huygen's Principle
Every point of a wave front serves as a point source of spherical, secondary waves. After a time t, the new position of the wave front will be that of a surface tangent to the secondary waves.
Huygens principle applies to any wavefront, even those that are curved as you would get from a single point source. A simple example of the Huygens Principle is to consider the single wavefront in the figure below.
A single wavefront at time t acts as a series of point sources of circular waves that interfere to give a new wavefront at a time \(t+\Delta t\). The process continues and applies to any shape of waveform.
Example: Application of the Huygen's Principle
Question
Given the wavefront,
use the Huygens Principle to determine the wavefront at a later time.
Step 1: Draw circles at various points along the given wavefront
Step 2: Join the circle crests to get the wavefront at a later time
This lesson is part of:
Introducing Electromagnetic Waves