1. Light and Color for the Middle School By Greg Corder

2. TOC 1.Reflection and mirrors 2.Refraction and lenses 3.Applications of lenses and mirrors 4.Color: light, pigments, and wavelength 5.Diffraction 6.Interference 7.Light the electromagnetic wave 8.Photoelectric effect 9.Nature of light: particle, wave, or both?

3. The Law of Reflection

4. Flat surfaces reflect best.

5. Curved Mirrors Concave mirrors converge light. Convex mirrors diverge light.

6. Concave Mirror Light converges. This means that it comes together. Also, the image is flipped past the focal point.

7. Convex Mirrors Light diverges. This means that light spreads out.

8. Curved Lenses Convex lenses converge light. The image is flipped past the focal point. Concave lenses diverge light.

9. Refractions causes light to bend. The shape of the lens determines how the light behaves.

11. Applications of lenses and mirrors

12. Periscope

15. Color

16. Dispersion … Color separates using a prism because different colors have different wavelengths. Red light bends the least and purple light bends the most.

17. Color depends on Wavelength of Light.

18. Colored lights combine to appear white.

19. Colored lights add to become white. Why then do paints add to become black?

20. Answer: paints are pigments. Pigments are chemicals which are capable of absorbing one or more frequency of white light.

21. Behaviors of light

22. Diffraction – a wave bends around an object Light is a wave!

23. Light through a small slit.

24. Interference: light is a wave!

26. Polarized light is a wave!

28. The Electromagnetic Spectrum Maxwell - (c. 1864) light is an EM wave

29. The photoelectric effect: light is a particle! The puzzle of intensity vs. energy

30. Einstein - (1905) –The duality theory of light –Light has a dual nature: light is both a particle and wave

31. Sources: http://www.glenbrook.k12.il.us/gbssci/phys/Class/BBoard.html http://www.mhhe.com/tillery Tillery, Physical Science. http://cougar.slvhs.slv.k12.ca.us/~pboomer/physicslectures/seco ndsemester/telescopes/refracting.jpg http://www.mhhe.com/tillery