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2. Standardized Test Prep Image and Math Focus Bank
Resources
Chapter Presentation
Bellringers
Transparencies
Standardized Test Prep
Image and Math Focus Bank
CNN Videos
Visual Concepts

3. Chapter 23 Table of Contents Section 1 Mirrors and Lenses
Light and Our World
Table of Contents
Section 1 Mirrors and Lenses
Section 2 Light and Sight
Section 3 Light and Technology

4. Chapter 23
Section 1 Mirrors and Lenses
Bellringer
What is the difference between a mirror and a lens? What is the difference between a convex mirror and a concave mirror? Can you think of one common use for a convex lens and for a concave lens?
Record your responses in your science journal.

5. Chapter 23
Section 1 Mirrors and Lenses
Objectives
Use ray diagrams to show how light is reflected or refracted.
Compare plane mirrors, concave mirrors, and convex mirrors.
Use ray diagrams to show how mirrors form images.
Describe the images formed by concave and convex

6. Rays and the Path of Light Waves
Chapter 23
Section 1 Mirrors and Lenses
Rays and the Path of Light Waves
A Ray of Light Because light waves travel in straight lines, you can use an arrow called a ray to show the path and the direction of a light wave.
Rays and Reflected and Refracted Light Rays help to show the path of a light wave after it bounces or bends.

7. Mirrors and Reflection of Light
Chapter 23
Section 1 Mirrors and Lenses
Mirrors and Reflection of Light
Plane Mirrors A plane mirror is a mirror that has a flat surface.
The reflection of an object in a plane mirror is right side up and the same size as the object, but reversed left to right.
Plane mirrors form virtual images. A virtual image is an image through which light does not travel

8. Chapter 23
Section 1 Mirrors and Lenses

9. Mirrors and Reflection of Light, continued
Chapter 23
Section 1 Mirrors and Lenses
Mirrors and Reflection of Light, continued
Concave Mirrors A concave mirror is a mirror that is curved inward.
The image formed by a concave mirror depends on the optical axis, focal point, and focal length of the mirror.

10. Chapter 23 The Optical Axis, Focal Point, and Focal Length
Section 1 Mirrors and Lenses
The Optical Axis, Focal Point, and Focal Length

11. Mirrors and Reflection of Light, continued
Chapter 23
Section 1 Mirrors and Lenses
Mirrors and Reflection of Light, continued
Concave Mirrors and Ray Diagrams Draw a ray diagram to determine if a concave mirror will form a virtual image like a plane mirror, or a real image.
A real image is an image through which light passes.

12. Chapter 23 How Images Are Formed in Concave Mirrors
Section 1 Mirrors and Lenses
How Images Are Formed in Concave Mirrors

13. Mirrors and Reflection of Light, continued
Chapter 23
Section 1 Mirrors and Lenses
Mirrors and Reflection of Light, continued
Convex Mirrors A convex mirror is a mirror that curves outward.
The image formed by a convex mirror is always virtual, right side up, and smaller than the original object.

14. Convex Mirror Ray Diagram
Chapter 23
Section 1 Mirrors and Lenses
Convex Mirror Ray Diagram

15. Lenses and Refraction of Light
Chapter 23
Section 1 Mirrors and Lenses
Lenses and Refraction of Light
A lens is a transparent object that forms an image by refracting, or bending, light. Two kinds of lenses are convex and concave.

16. Chapter 23 How Light Passes Through Concave and Convex Lenses
Section 1 Mirrors and Lenses
How Light Passes Through Concave and Convex Lenses

17. Lenses and Refraction of Light, continued
Chapter 23
Section 1 Mirrors and Lenses
Lenses and Refraction of Light, continued
Convex Lenses A convex lens is thicker in the middle than at the edges.

18. Lenses and Refraction of Light, continued
Chapter 23
Section 1 Mirrors and Lenses
Lenses and Refraction of Light, continued
Concave Lenses A concave lens is thinner in the middle than at the edges.

19. Chapter 23
Section 2 Light and Sight
Bellringer
Answer the following questions in your science journal.
What do you think a person who has colorblindness sees? If you have colorblindness, describe what you see.
What difficulties would a person who has colorblindness have?

20. Chapter 23
Section 2 Light and Sight
Objectives
Identify the parts of the human eye, and describe their functions.
Describe three common vision problems.
Describe surgical eye correction.

21. Chapter 23 How You Detect Light
Section 2 Light and Sight
How You Detect Light
Your eye gathers visible light to form the images that you see.
The thickness of the lens of the eye changes so that objects at different distances can be seen in focus. The light that forms a real image on the retina is detected by receptors called rods and cones.
The next slide explains how your eyes work.

22. Chapter 23
Section 2 Light and Sight

23. Common Vision Problems
Chapter 23
Section 2 Light and Sight
Common Vision Problems
Nearsightedness happens when a person’s eye is too long. A nearsighted person can see something clearly only if it is nearby. Faraway objects look blurry.
Farsightedness happens when a person’s eye is too short. A farsighted person can see faraway objects clearly. But things that are nearby look blurry.

24. Common Vision Problems, continued
Chapter 23
Section 2 Light and Sight
Common Vision Problems, continued
The images below explain how nearsightedness and farsightedness can be corrected with glasses.

25. Common Vision Problems, continued
Chapter 23
Section 2 Light and Sight
Common Vision Problems, continued
Color Deficiency is another name for colorblindness. The majority of people who have color deficiency can’t tell the difference between shades of red and green or can’t tell red from green.
Color deficiency happens when the cones in the retina do not work properly. Color deficiency cannot be corrected.

26. Surgical Eye Correction
Chapter 23
Section 2 Light and Sight
Surgical Eye Correction
Surgical eye correction works by reshaping the patient’s cornea by using a laser. Patients often gain perfect or nearly perfect vision after surgery.
Risks of Surgical Eye Correction Some patients report glares, double vision, or trouble seeing at night. People under 20 years old should not have surgical eye correction because their vision is still changing.

27. Chapter 23
Section 3 Light and Technology
Bellringer
Can you describe what a laser is? List at least four uses for lasers.
Explain your answers in your science journal.

28. Chapter 23 Objectives Describe three optical instruments.
Section 3 Light and Technology
Objectives
Describe three optical instruments.
Explain what laser light is, and identify uses for lasers.
Describe how optical fibers work.
Explain polarized light.
Explain how radio waves and microwaves are used in four types of communication technology.

29. Chapter 23 Optical Instruments
Section 3 Light and Technology
Optical Instruments
Optical instruments are devices that use mirrors and lenses to help people make observations.
Cameras A camera is used to record images. All cameras have a lens, shutter, and an aperture.
A 35 mm camera records images on film. A digital camera uses light sensors to record images and to send electric signals to a computer.

30. Chapter 23
Section 3 Light and Technology

31. Optical Instruments, continued
Chapter 23
Section 3 Light and Technology
Optical Instruments, continued
Telescopes Telescopes are used to see detailed images of large, distant objects.
Refracting telescopes use lenses to collect light.
Reflecting telescopes use mirrors to collect light.

32. Chapter 23 How Refracting and Reflecting Telescopes Work
Section 3 Light and Technology
How Refracting and Reflecting Telescopes Work

33. Optical Instruments, continued
Chapter 23
Section 3 Light and Technology
Optical Instruments, continued
Light Microscopes Microscopes are used to study tiny, nearby objects.
Microscopes have two convex lenses. An objective lens is close to the object being studied. An eyepiece lens is in the lens you look through.

34. Chapter 23 Lasers and Laser Light
Section 3 Light and Technology
Lasers and Laser Light
A laser is a device that produces intense light of only one wavelength and color.
How Lasers Produce Light The word laser stands for light amplification by stimulated emission of radiation. Amplification is the increase in the brightness of the light. Radiation is energy transferred as electromagnetic waves.

35. Chapter 23 Laser Light is Differs from Nonlaser Light
Section 3 Light and Technology
Laser Light is Differs from Nonlaser Light

36. Chapter 23
Section 3 Light and Technology

37. Lasers and Laser Light, continued
Chapter 23
Section 3 Light and Technology
Lasers and Laser Light, continued
Uses for Lasers Lasers are used to make holograms. A hologram is a piece of film that produces a three-dimensional image of an object.
Lasers have many other applications. They are used to cut materials such as metal and cloth. Doctors sometimes use lasers for surgery. CD players use lasers to read CDs.

38. Chapter 23 Optical Fibers
Section 3 Light and Technology
Optical Fibers
An optical fiber is a thin, glass wire that transmits light over long distances.
Optical fibers are used to transmit information through telephone cables and network computers. Doctors use optical fibers to see inside patients’ bodies.

39. Optical Fibers, continued
Chapter 23
Section 3 Light and Technology
Optical Fibers, continued
Light in a Pipe Optical fibers are like pipes that carry light. Light stays inside an optical fiber because of total internal reflection, the complete reflection of light light along the surface of the material.

40. Chapter 23
Section 3 Light and Technology

41. Chapter 23 Polarized Light
Section 3 Light and Technology
Polarized Light
Polarized light consists of light waves that vibrate in only one plane.
Some sunglasses and camera lenses use polarized filters to reduce glare.

42. Chapter 23 Polarizing Filters Reduce Glare
Section 3 Light and Technology
Polarizing Filters Reduce Glare

43. Communication Technology
Chapter 23
Section 3 Light and Technology
Communication Technology
Light waves, radio waves, and microwaves are all types of electromagnetic waves. Cordless telephones and cellular telephones use radio waves and microwaves to send signals.
Cordless Telephones The base of a cordless telephone changes the signal it receives into radio waves. The handset changes the radio waves into sound.

44. Communication Technology, continued
Chapter 23
Section 3 Light and Technology
Communication Technology, continued
Cellular Telephones Cellular telephones send and receives signals from distant towers. Instead of using radio waves like cordless phones, cellular phones use microwaves to send information.

45. Communication technology, continued
Chapter 23
Section 3 Light and Technology
Communication technology, continued
Satellite Technology Microwave signals are broadcast from space to satellite dishes on Earth.
Satellites allow more people to receive the signals and to receive higher quality signals than if antennas on Earth were used.
The Global Positioning System The GPS is a network of 27 satellites that orbit Earth. A GPS receiver receives signals from at least four satellites to find its exact location.

46. Chapter 23
Section 3 Light and Technology

47. Chapter 23
Light and Our World
Concept Map
Use the terms below to complete the concept map on the next slide.
real
convex
light
lenses
virtual
mirrors

48. Chapter 23
Light and Our World

49. Chapter 23
Light and Our World

50. End of Chapter 23 Show

51. Chapter 23
Standardized Test Preparation
Reading
Read each of the passages. Then, answer the questions that follow each passage.

52. Chapter 23
Standardized Test Preparation
Passage 1 One day in the 1920s, an automobile collided with a horse and carriage. Garrett Morgan witnessed this, and the accident gave him an idea. Morgan designed a signal that included signs to direct traffic at busy intersections. The signal could be seen from a distance and could be clearly understood. Morgan patented the first traffic signal in Unlike the small, three-bulb signal boxes used today, the early versions were T shaped and had the words stop and go printed on them.
Continued on the next slide

53. Chapter 23 Passage 1, continued
Standardized Test Preparation
Passage 1, continued
Morgan’s invention was an immediate success. Morgan sold the patent to General Electric Corporation for $40,000—a large sum in those days. Since then, later versions of Morgan’s traffic signal have been a mainstay of traffic control.

54. Chapter 23 1. In the passage, what does the word versions refer to?
Standardized Test Preparation
1. In the passage, what does the word versions refer to?
A automobiles
B accidents
C light bulbs
D traffic signals

55. Chapter 23 1. In the passage, what does the word versions refer to?
Standardized Test Preparation
1. In the passage, what does the word versions refer to?
A automobiles
B accidents
C light bulbs
D traffic signals

56. Chapter 23 2. Which of the following statements is a fact?
Standardized Test Preparation
2. Which of the following statements is a fact?
F Morgan still makes money selling traffic signals today.
G Traffic signals were confusing and caused a lot of accidents.
H Morgan came up with the idea of a traffic signal after seeing a traffic accident.
I Morgan patented the traffic signal in 1920.

57. Chapter 23 2. Which of the following statements is a fact?
Standardized Test Preparation
2. Which of the following statements is a fact?
F Morgan still makes money selling traffic signals today.
G Traffic signals were confusing and caused a lot of accidents.
H Morgan came up with the idea of a traffic signal after seeing a traffic accident.
I Morgan patented the traffic signal in 1920.

58. Chapter 23
Standardized Test Preparation
3. How were the first traffic signals similar to the signals used today?
A They were T shaped.
B They contained three light bulbs.
C The words stop and go were printed on them.
D They directed traffic at busy intersections.

59. Chapter 23
Standardized Test Preparation
3. How were the first traffic signals similar to the signals used today?
A They were T shaped.
B They contained three light bulbs.
C The words stop and go were printed on them.
D They directed traffic at busy intersections.

60. Chapter 23
Standardized Test Preparation
Passage 2 Twenty years ago, stars were very visible, even above large cities. Now, the stars above large cities are obscured by the glow from city lights. This glow, called sky glow, is created when light reflects off dust and particles in the atmosphere. Sky glow is also called light pollution.
Continued on next slide

61. Chapter 23 Passage 2, continued
Standardized Test Preparation
Passage 2, continued
The majority of light pollution comes from outdoor lights,such as headlights, street lights, porch lights, and parking-lot lights. Unlike other kinds of pollution, light pollution can easily be
reduced. For example, using covered outdoor lights keeps the light angled downward, which prevents most of the light from reaching particles in the sky. Also, using motion-sensitive lights and timed lights helps eliminate unnecessary light.

62. Chapter 23
Standardized Test Preparation
1. Which of the following best describes the reason the author wrote the passage?
A to explain light pollution and to explain how to reduce it
B to convince people to look at stars
C to explain why people should not live in cities
D to describe the beauty of sky glow

63. Chapter 23
Standardized Test Preparation
1. Which of the following best describes the reason the author wrote the passage?
A to explain light pollution and to explain how to reduce it
B to convince people to look at stars
C to explain why people should not live in cities
D to describe the beauty of sky glow

64. Chapter 23
Standardized Test Preparation
2. Which of the following contributes the least amount to light pollution?
F headlights on cars
G lights inside homes
H lights used in outdoor stadiums
I lights in large parking lots

65. Chapter 23
Standardized Test Preparation
2. Which of the following contributes the least amount to light pollution?
F headlights on cars
G lights inside homes
H lights used in outdoor stadiums
I lights in large parking lots

66. Chapter 23 3. In the passage, what does the word obscured mean?
Standardized Test Preparation
3. In the passage, what does the word obscured mean?
A made brighter
B reflected
C polluted
D made difficult to see

67. Chapter 23 3. In the passage, what does the word obscured mean?
Standardized Test Preparation
3. In the passage, what does the word obscured mean?
A made brighter
B reflected
C polluted
D made difficult to see

68. Interpreting Graphics
Chapter 23
Standardized Test Preparation
Interpreting Graphics
The table below shows details about four lasers sold by a laser company. Use the table below to answer the questions that follow.

69. Chapter 23 1. What is the mass of the laser that has the most power?
Standardized Test Preparation
1. What is the mass of the laser that has the most power?
A 0.6 kg
B 0.9 kg
C 2.8 kg
D 5.8 kg

70. Chapter 23 1. What is the mass of the laser that has the most power?
Standardized Test Preparation
1. What is the mass of the laser that has the most power?
A 0.6 kg
B 0.9 kg
C 2.8 kg
D 5.8 kg

71. Chapter 23
Standardized Test Preparation

72. Chapter 23
Standardized Test Preparation
2. The company also sells a laser that has a wavelength of 633 nm and a power of 5 mW. Which of the following statements best predicts the mass of this laser?
F The laser has a mass of less than 0.6 kg.
G The laser has a mass between 0.6 kg and 0.9 kg.
H The laser has a mass greater than 0.9 kg.
I The laser has a mass of 5.8 kg.

73. Chapter 23
Standardized Test Preparation
2. The company also sells a laser that has a wavelength of 633 nm and a power of 5 mW. Which of the following statements best predicts the mass of this laser?
F The laser has a mass of less than 0.6 kg.
G The laser has a mass between 0.6 kg and 0.9 kg.
H The laser has a mass greater than 0.9 kg.
I The laser has a mass of 5.8 kg.

74. Chapter 23
Standardized Test Preparation

75. Chapter 23
Standardized Test Preparation
3. Based on the information in the table, which statement is most likely true?
A The power of the laser determines the color of light.
B The wavelength of the laser determines the color of light.
C The mass of the laser determines the color of light.
D There is not enough information to determine the answer.

76. Chapter 23
Standardized Test Preparation
3. Based on the information in the table, which statement is most likely true?
A The power of the laser determines the color of light.
B The wavelength of the laser determines the color of light.
C The mass of the laser determines the color of light.
D There is not enough information to determine the answer.

77. Chapter 23 Math Read each question below, and choose the best answer.
Standardized Test Preparation
Math
Read each question below, and choose the best answer.

78. Chapter 23
Standardized Test Preparation
1. Micah has a box that has a length of 16 cm, a width of 10 cm, and a height of 5 cm. What is the volume of the box?
A 1,600 cm3
B 800 cm3
C 700 cm3
D 500 cm3

79. Chapter 23
Standardized Test Preparation
1. Micah has a box that has a length of 16 cm, a width of 10 cm, and a height of 5 cm. What is the volume of the box?
A 1,600 cm3
B 800 cm3
C 700 cm3
D 500 cm3

80. Chapter 23
Standardized Test Preparation
2. Which list shows the temperatures from lowest to highest?
F –3°C, 28°C, 212°C, 7°C, 11°C
G –3°C, 7°C, –8°C, 11°C, –12°C
H –12°C, 11°C, 7°C, –8°C, –3°C
I –12°C, –8°C, –3°C, 7°C, 11°C

81. Chapter 23
Standardized Test Preparation
2. Which list shows the temperatures from lowest to highest?
F –3°C, 28°C, 212°C, 7°C, 11°C
G –3°C, 7°C, –8°C, 11°C, –12°C
H –12°C, 11°C, 7°C, –8°C, –3°C
I –12°C, –8°C, –3°C, 7°C, 11°C

82. Chapter 23
Standardized Test Preparation
3. The power of a microscope lens is the amount of magnification the lens gives. For example, a 10x lens magnifies objects 10 times. How many times is an object magnified if it is viewed with both a 5x lens
and a 30x lens?
A 35 times
B 60 times
C 150 times
D 350 times

83. Chapter 23
Standardized Test Preparation
3. The power of a microscope lens is the amount of magnification the lens gives. For example, a 10x lens magnifies objects 10 times. How many times is an object magnified if it is viewed with both a 5x lens
and a 30x lens?
A 35 times
B 60 times
C 150 times
D 350 times

84. Chapter 23
Section 1 Mirrors and Lenses

85. Chapter 23 The Optical Axis, Focal Point, and Focal Length
Section 1 Mirrors and Lenses
The Optical Axis, Focal Point, and Focal Length

86. Chapter 23 How Images Are Formed in Concave Mirrors
Section 1 Mirrors and Lenses
How Images Are Formed in Concave Mirrors

87. Convex Mirror Ray Diagram
Chapter 23
Section 1 Mirrors and Lenses
Convex Mirror Ray Diagram

88. Chapter 23 How Light Passes Through Concave and Convex Lenses
Section 1 Mirrors and Lenses
How Light Passes Through Concave and Convex Lenses

89. Chapter 23
Section 1 Mirrors and Lenses

90. Chapter 23
Section 1 Mirrors and Lenses

91. Chapter 23
Section 2 Light and Sight

92. Chapter 23
Section 2 Light and Sight

93. Chapter 23
Section 3 Light and Technology

94. Chapter 23 How Refracting and Reflecting Telescopes Work
Section 3 Light and Technology
How Refracting and Reflecting Telescopes Work

95. Chapter 23 Laser Light is Differs from Nonlaser Light
Section 3 Light and Technology
Laser Light is Differs from Nonlaser Light

96. Chapter 23
Section 3 Light and Technology

97. Chapter 23
Section 3 Light and Technology

98. Chapter 23 Polarizing Filters Reduce Glare
Section 3 Light and Technology
Polarizing Filters Reduce Glare

99. Chapter 23
Section 3 Light and Technology

100. Chapter 23
Standardized Test Preparation

101. There is no Visual Concept correlated to this chapter.
Science in Our World
There is no Visual Concept correlated to this chapter.