1. Chapter 3– Electromagnetic Waves
3.1 The Nature of Electromagnetic Waves

2. I. Essential Question:
What is an electromagnetic wave?

3. II. Key Vocabulary
Electromagnetic wave: a transverse wave that involves electric and magnetic energy.
Electromagnetic radiation: the energy from electromagnet waves through space.
Polarized light: light that passes through a filter.
Photoelectric effect: when light moves so much energy it causes an electron to leave a metal.
Photon: a packet of light energy

4. III. Key Concepts
An EM wave is made up of vibrating electric and magnetic fields that move through space/medium at the speed of light.
The movement of charged particles creates a vibrating electric field, which then produces a vibrating magnetic field.
EM waves do not need a medium, so they can travel in a vacuum or empty space.

5. III. Key Concepts The wave model:
Ordinary light has waves that vibrate in all directions.
A polarizing filter creates tiny slits that allows light to only travel in one direction, resulting in polarized light.

6. III. Key Concepts The particle model:
Sometimes light behaves like a stream of particles.
The stream of particles, or photons, can have enough energy to knock electrons away from metals.

7. Chapter 3 – Electromagnetic Waves
3.2 Waves of the electromagnetic spectrum

8. I. Essential Question: How do electromagnetic waves compare?
What makes up the electromagnetic spectrum?

9. II. Key Vocabulary
Electromagnetic spectrum: complete range of EM waves in order of increasing frequency.
Radio waves: EM waves with the longest wavelengths and lowest frequencies.
Microwaves: next on the EM spectrum after radio waves.
Radar: system that uses reflected microwaves to detect objects and measure distance/speed.
Radio detection and ranging
Infrared rays: next on the EM spectrum after microwaves.

10. II. Key Vocabulary
Thermogram: an image that shows regions of different temps in different colors.
Visible light: EM waves you can see.
Ultraviolet rays: next on the EM spectrum after visible light.
X-rays: next on the EM spectrum after UV rays.
Gamma rays: the EM waves with the shortest wave length and highest frequency.

11. III. Key Concepts
All EM waves travel at the same speed in a vacuum, but they have different wavelengths and frequencies.
As the wavelength decreases, frequency increases.
Waves with a higher frequency also carry a higher energy.

12. III. Key Concepts
Infrared rays are sometimes called heat rays because you can feel the heat from them.
Warmer objects give off more energy than cooler objects.
Visible light that appears white is a mixture of all of the colors.
The visible light goes ROYGBIV – red has the longest wave length (least energy) of the colors.

13. III. Key Concepts
UV rays can damage or kill living cells with too much exposure, but are useful in causing skin cells to produce Vitamin D.
Dense matter absorbs X-rays, which stops it from passing through. This is why it is used to detect broken bones.
Gamma rays can be used to study internal structures of the body; too much is harmful to the body.

14. Chapter 3 – Electromagnetic Waves
3.3 Wireless Communication

15. I. Essential Question:
How do electromagnetic waves work with technology?

16. II. Key Vocabulary
Amplitude modulation: method of broadcasting signals by changing the amplitude of a wave (AM)
Frequency modulation: method of broadcasting signals by changing the frequency of a wave (FM)

17. III. Key Concepts
Radio waves carry info from the antenna at a broadcasting station to the antenna on your radio.
AM waves have a constant, low frequency and energy and can be broadcasted over long distances.
FM waves have a constant amplitude, high frequencies, and cannot travel as far as AM waves.

18. III. Key Concepts
Cell phones work because areas are divided into small cells which have one or more towers to relay signals to a central hub.
Cell phones work by transmitting and receiving high frequency microwaves.
Your cell phone service depends on terrain (why?) and how close you are to a tower/hub.

19. III. Key Concepts
Communication satellites receive and send signals to radio, TV, and telephone systems.
GPS uses a network of 24 satellites that broadcast radio waves to Earth.
Signals from 4 out of 24 satellites are used to detect your location; 3 of them tell where you are and 1 tells how far above Earth’s surface you are.

20. Chapter 4 – Light
4.1 Light and Color

21. I. Essential Question:
What determines color?
How do colors combine?

22. II. Key Vocabulary Transparent: a material that allows light through
Translucent: a material that allows some light through
Opaque: a material that does not allow light through

23. II. Key Vocabulary
Primary color: colors that combine to make any other color.
Secondary color: colors created by two primary colors.
Complementary color: any two colors that combine to form white light.
Pigment: colored substances used to color other materials.

24. III. Key Concepts
The color of an opaque object is the color of the light that it reflects.
Objects can appear to change color if they are viewed in different colors of light.
The color of transparent or translucent objects is the color that it transmits.
Used to make color filters.

25. III. Key Concepts
Primary colors of light – red, green, and blue; when they are combined equally they form white light.
Secondary colors of light – yellow (red/green), cyan (green/blue), and magenta (red/blue).
Primary + secondary = white light

26. III. Key Concepts
The more pigments that are combined, the darker the mixture looks.
Cyan, magenta, and yellow are the primary colors of pigments.
When combined equally, they make black.
Red, green, and blue are the secondary colors of pigments.

27. IV. Exploration

28. V. Understanding and Applying

29. 4.2 Reflection and Mirrors
Chapter 4 – Light
4.2 Reflection and Mirrors

30. I. Essential Question: What are the kinds of reflection?
What types of images do mirrors produce?

31. II. Key Vocabulary Ray: light waves as straight lines
Regular Reflection: parallel rays of light hit a smooth surface
Image: copy of an object
Diffuse Reflection: parallel rays of light hit an uneven surface

32. II. Key Vocabulary
Plane Mirror: a flat sheet of glass that has a smooth, silver-colored coating on one side.
Virtual Image: an image that forms from where light seems to come from.
Concave mirror: mirror with an inward curving surface
Optical axis: imaginary line that divides a mirror in half

33. II. Key Vocabulary Focal point: the point where rays meet
Real image: forms when light rays actually meet
Convex mirror: mirror with an outward curving surface.

34. III. Key Concepts
The angle of reflection equals the angle of incidence.
Metal, glass, and calm water create a regular reflection, in which the image is clear.
In diffuse reflection, you either see an unclear image or no image at all.

35. III. Key Concepts
A plane mirror creates a virtual image that is upright and the same size as the object, but the left and right are reversed.
Concave mirrors produce real (when the object is farther away) or virtual images (when the object is between the mirror and focal point).
Real images are upside down, and can be the same size, smaller, or larger than the object.

36. III. Key Concepts
Virtual images from a concave mirror are always larger.
A convex mirror produces a virtual image that is always smaller than the object.

37. IV. Exploration

38. V. Understanding and Applying

39. Chapter 4 – Light
4.3 Refraction and Lenses

40. I. Essential Question:
What causes light rays to bend?

41. II. Key Vocabulary
Index of refraction: a measure of how much a light ray bends when it enters a medium
Mirage: an image of a distance object caused by refraction of light.

42. III. Key Concepts
When light passes from one medium to another, it bends, or refracts because it moves at a new speed.
Light travels fastest in air, a little slower in liquids, and slowest in solids.
A higher index of refraction means the light is being bent more.

43. III. Key Concepts
Colors with longer wavelengths refract less when put through a prism.
Red has the longest wavelength and bends the least; violet has the shortest wavelength and refracts the most.
In a rainbow, water droplets act like tiny prisms, reflecting/refracting the light.

44. III. Key Concepts
The more pigments that are combined, the darker the mixture looks.
Cyan, magenta, and yellow are the primary colors of pigments.
When combined equally, they make black.
Red, green, and blue are the secondary colors of pigments.

45. IV. Exploration

46. V. Understanding and Applying

47. Chapter 4 – Light
4.3 Refraction and Lenses

48. I. Essential Question:
What determines the type of image produced by a lens?

49. II. Key Vocabulary Lens: curved piece of glass that refracts light.
Concave lens: a lens that is thinner in the center and wider along the edges.
Convex lens: a lens that is thicker in the center and thinner along the edges.

50. III. Key Concepts Concave lens:
When light rays pass through, they bend away from one another and never meet.
Always produces a virtual image that is upright and smaller than the object.

51. III. Key Concepts Convex lens:
When light rays pass through it, they bend toward one another and meet at the focal point.
The more curved the lens, the more if refracts light.
When an object is between the lens and the focal point, a virtual image is created.
Larger than the object
When the object is outside of the focal point, a real image is created.
Smaller, larger, or same size as the object.

52. IV. Exploration

53. V. Understanding and Applying

54. Chapter 4 – Light
4.4 Seeing Light

55. I. Essential Question:
How do you see objects?

56. II. Key Vocabulary Cornea: surface of the eye
Pupil: the black part of the eye
Iris: the colored part of the eye; muscular ring
Retina: layer of cells lining the inside of the eyeball
Rods: cells that contain a pigment that responds to small amount of light (see in dim light)

57. II. Key Vocabulary
Cones: cells that respond to color (respond best in bright light)
Optic nerve: thick nerve that sends signals to the brain
Nearsighted: can see nearby objects clearly
Farsighted: can see distant objects clearly

58. III. Key Concepts Light enters through the cornea and then the pupil.
In darkness, the pupil expands to let more light in; in light, it contracts to decrease the amount of light.
The iris controls the size of the pupil.
After the pupil, light passes through a convex lens.

59. III. Key Concepts
An upside-down image is formed on the retina, which contains the rods and cones.
These send the image through the optic nerve to the brain.
Your brain interprets the image as an upright image.

60. III. Key Concepts
In a nearsighted person, the eyeball is too long, so a concave lens is used to spread out light rays.
In a farsighted person, the eyeball is too short, so a convex lens is used to bend the light rays together.

61. IV. Exploration

62. V. Understanding and Applying

63. Chapter 4 – Light
4.5 Using Light

64. I. Essential Question:
How is light used in technology?

65. II. Key Vocabulary Camera: records an image of an object.
Telescope: forms enlarged images of distant objects.
Refracting telescope: consists of two convex lenses.
Objective: gathers the light coming from an object and forms a real image

66. II. Key Vocabulary Eyepiece: magnifies an image in a telescope
Reflecting telescope: uses a large concave mirror
Microscope: forms enlarged images of tiny objects

67. III. Key Concepts
The lenses in a camera focus light to form a real, upside-down image in the back of the camera.
Telescopes use lenses or mirrors to collect and focus light from distant objects.
A microscope uses a combo of lenses to produce and magnify and image.

68. IV. Exploration

69. V. Understanding and Applying