1. Calculate the speed of a water wave when waves 5.0 m apart pass by at 40.0 waves per minute

2. Chapter 16 Light

3. The range of frequencies of electromagnetic waves that stimulate the retina of the eye

4. Electromagnetic Wave Transverse waves made up of pulses moving through space that affect both electric & magnetic fields

5. Spectrum An ordered arrangement of many frequencies or wavelengths of waves

6. Electromagnetic Spectrum An ordered arrangement of all the electromagnetic waves

7. Ray The straight line path of a light wave

8. Incident Ray A ray striking a surface

9. Transmitted Ray A ray passing through a substance

10. Reflected Ray A ray bouncing off of another substance

11. Speed of Light First Determined by Ole Roemer by observing the moons of Jupiter from opposite ends of Earth’s orbit.

12. Speed of Light Correctly determined by Michelson by reflecting light from a spinning octagonal mirror.

13. Speed of Light c vac = 299,792,458 m/s For most calculations: c = 3.00 x 10 8 m/s

14. Light Velocity Formula: c = f

15. Calculate the frequency of electromagnetic waves at: 600.0 nm 150  m 45.0 cm

16. Calculate the frequency of IR light at: 900.0 nm

17. Luminous Anything that emits light Sun, light bulb, etc

18. Illuminated Anything that reflects light Moon, mirror, wall, etc

19. Luminous Flux (P) The rate at which light is emitted

20. Lumens (lm) The unit of luminous flux

21. Light from a bulb or source is emitted spherically from the source

22. We are usually interested in the illumination of a certain area

23. Illuminance (E) The illumination of a surface

24. Lux (lx) The unit for illumination lx = lm/m 2

25. Luminous Intensity (I) The magnitude of the light source

26. Candela (cd) Candle power of the unit for luminous intensity

27. Luminous Intensity Formula I d 2 E =

28. Luminous Flux Formula P 4  d 2 E =

29. Determine the effect on illumination of a wall if a light source is moved from 30.0 to 120 cm away from the wall.

30. Calculate the illumination on a surface 2.0 m away from a bulb emitting 1600 cd.

31. Calculate the illumination on a surface 3.0 m away from a bulb emitting 2700 cd.

32. Transparent Substances that allows light to be clearly transmitted through them

33. Translucent Substances that allows light to be transmitted, though not clearly, through them

34. Opaque Substances absorb or reflect all light striking them

35. Color A perception caused when cones in the eyes are excited by certain frequencies or wavelengths of electromagnetic waves

36. Luminous Colors

37. Primary Colors Red Blue Green

38. Secondary Colors Colors produced by mixing primary colors

39. Secondary Colors Yellow = Red + Green Cyan = Blue + Green Magenta = Red + Blue

40. Complimentary Colors Two colors that when mixed produced white light

41. Complimentary Colors Red + Cyan Blue + Yellow Green + Magenta

42. List the three primary colors & list each’s complementary color.

43. Illuminated Colors

44. Dyes Molecules that absorb certain wavelengths of light; thus reflect others

45. Dyes Dyes are made up of molecules which are too small to be seen with a microscope

46. Dyes When dissolved, form colored solutions that allow light to pass through

47. Pigments Materials that absorb certain wavelengths of light; thus reflect others

48. Pigments Pigments are made up of particles large enough to be seen with a microscope

49. Pigments When dissolved, form suspensions that reflect light and are opaque

50. Primary Pigments A pigment that absorbs a primary color

51. Primary Pigments Yellow Cyan Magenta

52. Secondary Pigments A pigment that absorbs two primary colors; thus reflect the third

53. Secondary Pigments They are the primary colors: red, blue, & green

54. Thin Film Interference Constructive & destructive effects of interference causing a rainbow appearance on a thin film

55. Thin Film Interference Wavelengths are reinforced when the film is ¼, ¾, 5/4, etc

56. Electromagnetic waves are transverse with vibrations like sin waves vibrating at 360 o from the ray

57. Polarized Light A light wave vibrating in only one direction

58. Polarized Light Can be produced by passing regular light through a polarized lens

59. Polarizer A screen with very fine slits all being parallel to each other

60. Calculate the frequency & period of light with a wavelength of 450 nm