Huygens Principle

Huygens Principle

1. Huygens Principle

2. What is it? Method of analysis applied to problems using wave propagation Source: Wikipedia pictures

3. Proposal 1678 from Christiaan Huygens Every point on a wave-front may be considered a source of secondary spherical wavelets which spread out in the forward direction at the speed of light. The new wave-front is the tangential surface to all of these secondary wavelets . ( farside.ph.utexas.edu) Assumed that secondary waves only travelled in “forward” direction Provided a qualitative explanation of linear and spherical wave propagation Derived the laws of reflection and refraction Couldn’t explain the diffraction aspect

4. HYGUYENS Principle Steps in how to apply: Start anywhere of the original wave-front. Draw a circle with any radius. Repeat for the rest of the points you choose with the same radius. You now have your new wave-front

5. Not only light waves Interference works for all different waves Can show how a ray travels from one medium to another The figure shows how refractions works Ray will refract since it’s a different medium

6. Reflection Can see how the rays would be reflected Same pattern would happen Rays are reflected downwards because the angle of the mirror is pointed downwards Originally moving from left to right

7. Sources http:// farside.ph.utexas.edu/teaching/302l/lectures/node150.html http:// physics.about.com/od/mathematicsofwaves/a/huygensprincipl.htm https://www.boundless.com/physics/textbooks/boundless-physics-textbook/wave-optics-26/diffraction-175/huygens-principle-636-5593 / http :// www.mathpages.com/home/kmath242/kmath242.htm