LlIGHT REVIEW PART 2 DOWNLOAD, PRINT and submit for 100 points

Transcription

1 WRITE ON SCANTRON WITH NUMBER 2 PENCIL DO NOT WRITE ON THIS TEST LlIGHT REVIEW PART 2 DOWNLOAD, PRINT and submit for 100 points Multiple Choice Identify the choice that best completes the statement or answers the question. 1. In 1926, Michelson was able to measure the speed of light using a. lanterns. c. mirrors. b. stars. d. sunlight. 2. An electromagnetic wave in a vacuum has a wavelength of 0.07 m. What is its frequency? a. f = m/s c. f = Hz b. f = Hz d. f = m/s 3. Light acts like a. a wave. c. both a wave and a particle. b. a particle. d. neither a wave nor a particle. 4. Photons travel outward from a light bulb in a. a single straight line. c. a small, dense area. b. increasing intensity. d. all directions. 5. Which of the following occurs as light travels farther from its source? a. Far from the source, photons come together in a small area. b. The intensity of light increases as photons move away from the source. c. The source gives off less light as photons move away from it. d. Far from the source, photons spread over a larger area. 6. Infrared rays have a shorter wavelength than a. ultraviolet rays. c. radar waves. b. X-rays. d. gamma rays. 7. The full range of frequencies of electromagnetic radiation is called a. visible light. c. the electromagnetic spectrum. b. radio waves. d. invisible radiation. 8. Cellular telephones utilize a. radar waves. c. very low frequency waves. b. very high frequency waves. d. microwaves. 9. X-ray photographs show softer tissue a. as invisible. b. as dark, highly exposed areas. c. the same as dense bones. d. as bright white areas. 10. A translucent material a. scatters some light. c. absorbs all light. b. transmits all light. d. reflects all light. 11. In order of increasing light-transmitting capabilities of materials, which is the correct sequence? a. transparent opaque translucent b. opaque transparent translucent c. opaque translucent transparent d. translucent transparent opaque 1

2 12. Newton s prism experiments showed that white sunlight is made up of a. the full electromagnetic spectrum. b. only blue light. c. all the colors of the visible spectrum. d. only the longest wavelengths. 13. When droplets of water in the atmosphere act like prisms, the colors in sunlight undergo a. interference. c. polarization. b. absorption. d. dispersion. 14. What an object is made of and the color of light that strikes it determine the a. apparent color of the object. b. transparency of the object. c. opacity of the object. d. translucence of the object. 15. Blue light and yellow light combine to produce white light because a. they absorb each other s wavelengths. b. blue, yellow, and white are primary colors. c. they are complementary colors of light. d. they are both primary colors of light. 16. The primary colors of light are a. green, blue, and black. b. cyan, magenta, and yellow. c. red, yellow, and blue. d. blue, green, and red. 17. The primary colors of pigments a. are cyan, yellow, and magenta. b. are the same as the secondary colors of light. c. combine in equal amounts to produce black. d. all of the above 18. Which of the following is NOT true regarding neon lights? a. Light is emitted as electrons move through a gas in a tube. b. All neon lights are colored by the color of the tubing. c. Neon lights may contain other gases, such as helium or krypton. d. Each kind of gas produces its own distinctive color. 19. A fluorescent light tube usually contains a. a vacuum. c. mercury vapor. b. oxygen. d. light-emitting diodes. 20. Which kind of light is used to carry information through optical fibers? a. incandescent c. sodium-vapor light b. fluorescent d. laser 21. For reflection off a plane mirror, the angle of incidence a. is greater than the angle of reflection. b. is less than the angle of reflection. c. equals the angle of reflection. d. changes the angle of reflection. 2

3 22. What is the angle of reflection? a. the angle that the incident ray makes with a line drawn perpendicular to the reflecting surface b. the angle that the reflected ray makes with a line drawn perpendicular to the reflecting surface c. the angle the reflecting surface makes with the ground d. the angle that the reflected ray makes with the incident ray 23. The law of reflection states that if the angle of incidence is 45 degrees, the angle of reflection is a. 90 degrees. c. 45 degrees. b degrees. d. 135 degrees. 24. A mirror with a flat surface is a a. plane mirror. c. concave mirror. b. convex mirror. d. virtual mirror. 25. In a plane mirror, reflected light rays appear to come from a. in front of the mirror. b. an angle above the mirror. c. a distance behind the observer. d. behind the mirror. Figure What is the point called at which the reflected rays intersect in Figure 19-1? a. virtual image c. focal point b. plane image d. illumination point 27. A convex mirror can form a. both virtual and real images. c. only virtual images. b. only real images. d. none of the above 28. Why do plane mirrors and convex mirrors form only virtual images? a. because they only reflect light b. because they cannot make light rays converge c. because the focal point is in front of the mirror d. because they both show a wide angle of view 3

4 29. Light refracts when it a. bounces off a surface. c. comes from a laser. b. changes speed. d. spreads out from its source. 30. Because air causes light to slow only slightly, air s index of refraction is a. low. c. moderate. b. high. d. nonexistent. 31. A concave lens can only form a a. real image. c. virtual image. b. reversed image. d. magnified image. 32. Light can be transmitted through long fiber optic strands because of a. refraction. c. total internal reflection. b. external diffraction. d. interference. 33. Total internal reflection occurs when the angle of incidence a. is zero. c. exceeds the critical angle. b. is less than the critical angle. d. equals the angle of reflection. 34. Which optical instrument uses a large concave mirror, a plane mirror, and a convex lens to gather light, focus, and enlarge an image? a. refracting telescope c. reflecting telescope b. microscope d. film camera 35. Which statement is correct regarding a refracting telescope? a. It produces an enlarged real image. b. It produces an enlarged virtual image. c. It produces a reduced-size image. d. It produces a small, upside-down image. Completion Complete each statement. 36. Electromagnetic waves are waves consisting of changing electric and magnetic fields. 37. Warm objects give off more radiation than cool objects give off. 38. The speed of light in a vacuum is m/s. 39. The farther away you are from a light source, the intense it appears. 40. Objects that scatter some of the light that is transmitted through them are. 41. When viewed in yellow light, an object that reflects all the colors of light will appear. 42. Combining equal amounts of the three primary pigments produces. 43. Electromagnetic waves can travel through a(an). 44. Light is produced when change energy levels in an atom. 45. Microwaves have a higher than radio waves have. 46. A transparent object almost all of the light that strikes it. 4

5 47. The electromagnetic waves with the shortest wavelengths are rays. 48. An ultraviolet light wave has a wavelength of 200 nm and a frequency of Hz. The ultraviolet light is NOT traveling through a(an). 49. In microwave cooking, heating only occurs near the of the food. 50. A mirage, or distorted image, can be caused by the of light as it moves into layers of hotter and hotter air. 51. White light passing through a prism separates into colors because of the differences in the of each color of light. Figure The electromagnetic waves shown in Figure 18-1 are an example of used in certain radio broadcasts. 53. Light amplification by stimulated emission of radiation is known as light. 54. To form white light from the combination of only two colors of light, the colors must be. 55. The following electromagnetic waves are arranged in order of increasing frequency: infrared,, ultraviolet. 56. The law of reflection states that the angle of reflection is equal to the angle of. 57. The angles of incidence and reflection are the angles that rays make relative to a line drawn to the surface of a mirror. 58. The image that appears to be in front of a concave mirror is a(an) image. 5

6 Figure The mirror in Figure 19-1 is a(an) mirror. 60. The type of image that can be projected on a screen is a(an) image. 61. Mirrors that curve outward are called mirrors. 62. A bowl shape that could hold water can be described as having a(an) shape. 63. When light exits a vacuum and enters any other medium, it. 64. A material s index of refraction is a measure of how the speed of light in that material slows compared to the speed of light in a(an). 65. Light rays passing through a convex lens converge at the point on the opposite side of the lens that they enter. 66. Light rays are generally unable to through the sides of curving fiber optic strands. 67. The greater a material s the more likely it is that light passing through the material will be totally internally reflected. 68. Unlike a reflecting telescope, a refracting telescope uses a series of to focus light from distant objects. 69. Like a human eye, a film camera has a convex that forms an upside-down image. 70. The light source for a compound microscope can be either an electric light or light reflected from a(an). 71. The objective of a refracting telescope produces a small, upside-down, image. 72. The iris controls the amount of light entering the eye by adjusting the size of the. 73. Nerve endings in the retina that are most sensitive to low-intensity light are called. 74. Nerves on the retina that are sensitive to color are called. 75. Nearsightedness results when light rays from distant objects focus in front of the. 6

7 Short Answer 76. What is a basic difference between electromagnetic waves and sound waves? Figure Why is the amplitude of the radio wave in Figure 18-1 varied? 78. In which medium does light travel faster, air or glass? 79. What is the photoelectric effect? 80. Describe what happens to photons as they travel away from a light source. 81. Which type of electromagnetic wave has the longest wavelength and lowest frequency? 82. Both gamma rays and X-rays are used to see inside the body. Which one is used to make images of bones? How are the other rays used? 83. Which waves have wavelengths longer than those of visible light? Give an example of how each kind of wave is used. 84. How would you describe a translucent material? 85. Use the scattering of light to explain why the sun is red at sunset. 86. What type of light passes through a polarizing filter? 87. What two factors influence the color of an object? 88. Magenta is a secondary color of light. What type of color is magenta when it is a pigment? 89. What is common to all light sources including incandescent, fluorescent, neon, halogen, laser, and sodium-vapor devices? 90. What distinguishes a laser from other common light sources? 91. What is the usual method of graphically analyzing how light rays behave when they strike mirrors or pass through lenses? 92. What determines the type of image produced in a concave mirror? 93. Water has an index of refraction of 1.33, and glass has an index of refraction of Which refracts light more and why? 7

8 94. How is the index of refraction of a material related to the speed of light? 95. Explain why convex lenses are also called converging lenses. 96. What is the principle that makes fiber optics able to transmit data in the form of light pulses over long distances with little loss in signal strength? 97. Why must a microscope slide be made of a transparent material like glass if the glass does not magnify the image? 98. How many and what kind of lenses does a compound microscope use to magnify small objects? 99. What are two causes of farsightedness? Problem 100. A communications satellite transmits a radio wave at a frequency of Hz. What is the signal s wavelength? Assume the wave travels in a vacuum. Show your work. 8