Download
ch 19 light n.
Skip this Video
Loading SlideShow in 5 Seconds..
Ch. 19 - Light PowerPoint Presentation
Download Presentation
Ch. 19 - Light

Ch. 19 - Light

157 Vues Download Presentation
Télécharger la présentation

Ch. 19 - Light

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Ch. 19 - Light III. Wave Properties of Light (p.546-550) • Reflection • Refraction • Diffraction • Interference

  2. Normal incident beam reflected beam A. Reflection • Reflection • when a wave strikes an object and bounces off

  3. A. Reflection • Law of Reflection • the angle of incidence equals the angle of reflection

  4. SLOWER FASTER B. Refraction • Refraction • bending of waves when passing from one medium to another • caused by a change in speed • slower (more dense) light bends toward the normal • faster (less dense) light bends away from the normal

  5. B. Refraction • Refraction depends on… • speed of light in the medium • wavelength of the light - shorter wavelengths (blue)bend more

  6. B. Refraction • Example: View explanation.

  7. C. Diffraction • Diffraction • bending of waves around a barrier • longer wavelengths (red) bend more - opposite of refraction

  8. D. Interference • Interference • constructive  brighter light • destructive  dimmer light

  9. E. Cool Applications! • Fiber Optics • Total Internal Reflection • when all light is reflected back into the denser medium

  10. E. Cool Applications! • The “Broken Pencil” • refraction View animation and explanation of the “Broken Pencil.”

  11. E. Cool Applications! • Rainbows • refraction-reflection-refraction

  12. E. Cool Applications! • Diffraction Gratings • glass or plastic made up of many tiny parallel slits • may also be reflective • spectroscopes, reflective rainbow stickers, CD surfaces

  13. E. Cool Applications! • Thin Films - Bubbles & Oil Slicks • interference results from double reflection

  14. E. Cool Applications! • Blue Sky & Red Sunsets • Molecules in atmosphere scatter light rays. • NOON • less atmosphere • less scattering • blue sky, yellow sun • Shorter wavelengths (blue, violet) are scattered more easily. • SUNSET • more atmosphere • more scattering • orange-red sky & sun