Name: Date: Block: Light Unit Study Guide Matching Match the correct definition to each term. 1. Waves 2. Medium 3. Mechanical waves 4. Longitudinal waves 5. Transverse waves 6. Frequency 7. Reflection 8. Refraction 9. Electromagnetic waves 10. Index of Refraction a. When waves bounce off of solid objects. b. Type of mechanical wave that vibrates up and down or right to left as it moves perpendicular to the motion of the medium. c. Waves that require a medium to travel through. d. The bending or changing direction of waves as it goes through a different medium due to a change in speed. e. The rate at which a wavelength occurs/ repeated over a period of time. f. The matter through which a mechanical wave travels. g. Waves that do not require a medium to travel through. h. Traveling disturbance that carries energy from one place to another. i. Type of mechanical wave that moves in and out as a series of compressions and rarefactions and parallel to the motion of the medium. j. Measure of how much a ray of light bends when it passes from one medium to another. True and False: Identify the following statements as either True or False. If the statement is false, correct the wrong word. 11. Nearsightedness is a condition that occurs when the eye is too long and the light rays focus in front of the retina, causing the person to see nearby objects clearly, but distant objects blurry. 12. The optic nerve is a short, thick nerve that carries the signals in the retina from the eye to the brain. 13. Rod cells respond to and detect colors.
14. The iris is the ring of muscle that controls how much light enters the eye through the expansion and contraction of the pupil. It also gives the eye its color. 15. The retina is the transparent tissue that bends or refracts light passing through the eye and helps focus an image on the retina. 16. The cornea is the transparent or clear membrane that covers the front surface of the eye. 17. The pupil is the hole or opening in the center of the iris, through which light enters the eye. 18. The lens is the layer of tissue that lines the inside of the eyeball. It consists of nerve cells and fibers which gather information. 19. Farsightedness is a condition that occurs when the eye is too short and the light rays focus behind the retina, causing the person to see distant objects clearly, but nearby objects blurry. 20. The color of an opaque object is the color of light it transmits, while the color of a transparent or translucent object is the color of the light it reflects. 21. A wave is a traveling disturbance that carries energy from one point to another, without transferring matter between the points. 22. Telescopes are used to magnify tiny objects such as cells. Fill-in-the-Blank Fill in the blank with the term that correctly completes the sentence. 23. Used in remotes to change the channels on your TV, as well as surveillance cameras and heat radiators. 24. Found in space, nuclear explosions, and lightning; used in medicine to kill cancer cells and sterilize medical equipment. 25. Strong enough to penetrate deep into tissues and take images of your teeth, bones, and other objects. 26. Only part of the spectrum that is visible to the human eye; contains the colors of the rainbow and is used for laser printers. 27. Primarily used to broadcast or transmit radio and television signals as well as cell phone signals.
28. Occurs naturally in sunlight and most of it is blocked by the ozone layer; can be absorbed by the skin and is used in fluorescent light bulbs and tanning beds. 29. Used in cooking, radar systems, telephone, and other signals. 30. Highest point of a wave (peak). 31. Lowest point of a wave. 32. Distance between 2 corresponding points on a wave. 33. Height of a wave, distance between crest and rest line. 34. When crests of longitudinal wave are close together. 35. When crests of longitudinal wave are spread far apart. 36. Three colors of light that can be combined to make any other color (i.e. red, blue, and green). 37. Used by microscope and refracting telescopes to produce a magnified image. 38. Image of a distant object caused by refraction of light. 39. 3-D photograph created using lasers. Multiple Choice Questions 40. How fast do electromagnetic waves travel? a. At the speed of light c. Faster than the speed of light b. At the speed of sound d. Slower than the speed of sound 41. Which type of electromagnetic radiation carries the most energy and has the highest frequency? a. Microwaves c. Gamma rays b. Ultraviolet d. Radio waves 42. How are different types of radiation arranged along the electromagnetic spectrum? a. By how fast they travel. c. By amount of energy they carry. b. By their sources. d. By how radioactive they are. 43. What do all forms of electromagnetic radiation have in common? a. Their strength. c. Their wavelength. b. Their speed. d. Their frequency.
44. An object can be classified into one of three materials depending on what occurs when light strikes it:,, and. a. Transparent, transmission, and opaque b. Reflected, absorbed, and transmitted c. Transparent, translucent, and opaque d. Reflected, absorbed, and opaque 45. When you combine all the colors of the light spectrum, what do we see? a. Black b. White c. Red, blue, and green d. Nothing 46. When light strikes an object, the light can be,, and. a. Reflected, transmitted, and opaque b. Reflected, transmitted, and absorbed c. Reflected, translucent, and absorbed d. Translucent, transparent, and transmitted 47. What are the two types of mechanical waves? a. Longitudinal waves and transverse waves b. Longitudinal waves and electromagnetic waves c. Transverse waves and electromagnetic waves d. Electromagnetic waves and mechanical waves 48. Which best explains the relationship between the electromagnetic spectrum and sight? a. Visible light is the part of the electromagnetic spectrum that can be seen with the eye. b. Ultraviolet light is the part of the electromagnetic spectrum that can be seen with the eye. c. Visible light and infrared light are the parts of the electromagnetic spectrum that can be seen with the eye. d. Ultraviolet light and infrared light are the parts of the electromagnetic spectrum that can be seen with the eye. 49. What is the relationship between eyesight and light? a. Light shines on all objects, allowing people to see the object. b. Light shines through all objects, allowing people to see the object. c. Light enters the eye before striking the object, allowing people to see the object. d. Light reflects off an object and then enters the eye, allowing people to see the object. 50. Place the steps in order to answer the question: How do we see? Light then passes through the lens, which refracts or bends the light onto the lining of the eyeball, also known as the retina, causing the image to be upside down.
Optic nerve sends the signals to the brain, which interprets the image by turning it right side up. Light enters the eye through a transparent covering called the cornea. Cells on the retina called rods and cones change the light into electrical signals. Light continues through the pupil, an opening in the eyeball, which is controlled by the iris.
Label the following diagrams. 51. Transverse Wave Z Y X 52. Longitudinal Wave M V 53. Electromagnetic Spectrum P Energy Energy 54. Eye Diagram
Short Answer Questions (2-3 sentences) Answer the following questions to the best of your ability. Make sure to answer every component of the questions and to incorporate the appropriate vocabulary terms. 55. How are mechanical waves different from electromagnetic waves? 56. What is the difference between a diffused reflection and a regular reflection? What type of image is produced by each? 57. Compare and contrast convex and concave lenses. What type of lens is the human eye? What kind of image does each lens produce? 58. Compare and contrast virtual and real images. 59. Compare and contrast plane, concave, and convex mirrors. 60. Describe the difference between a transparent, translucent, and opaque object.