CHAPTER 22 (LIGHT & EM) EM41. An electromagnetic wave is made up of which of the following oscillating quantities? a. electrons only b. electric fields only c. magnetic fields only d. electric and magnetic fields EM42. In order of increasing frequency, which of the following is correct? a. visible, radio,ultraviolet and X-ray b. infrared, visible, ultraviolet and gamma c. visible, gamma, ultraviolet and X-ray d. infrared, X-ray, visible and gamma EM44. A radar pulse returns 3.0 10-4 seconds after it is sent out when reflected from an object. What is the distance between the radar and object? (c = 3 108 m/s) a. 9.0 104 m b. 4.5 104 m c. 6.0 104 m d. 1.0 104 m EM45. In order to keep its food hot, a restaurant will place it under which type of lamp? a. infrared b. visible light c. ultraviolet d. X-ray EM46. Glass panes are opaque to a certain type of radiation which passes through quartz. What type of radiation is it? a. microwave b. gamma c. X-ray d. ultraviolet E at a 45˚ angle to B EM53. E. Hertz b. Which one of the following scientists first built and operated devices that could emit and detect man-made electromagnetic radiation? a.4 10-2 m EM54. 4. moves parallel to a uniform magnetic field EM50.8 m d. The electric field. Maxwell d. E parallel to B b.EM47. E anti-parallel to B c.2 MHz has what wavelength? (c = 3 108 m/s) a. moves at constant velocity b. 41. Which condition of motion must be met with regard to a charged particle if it is in the process of emitting electromagnetic radiation? a. Faraday c. 2. E perpendicular to B d. B? a. Which one of the following scientists made the theoretical prediction that electromagnetic waves travel through a vacuum at the speed of light? a. in an electromagnetic wave is oriented in what direction with respect to its associated magnetic field.7 m b. Hertz b. A radio wave signal which transmits at a frequency of 7. moves at the speed of light d. A radar pulse sent out to an airplane at a distance of 20 km will return as an echo to the source in what time interval? (c = 3 108 m/s) . accelerates c. Maxwell d.2 m c. 28. Lenz EM49. Lenz EM48. Ampere c. 33.a.5 108 Hz c. 133 10-6 s d. 66. 0. aircraft navigation d.1 1011 Hz d. 9 102 Hz c. Temperature variation of different parts of a person’s body can be detected by analyzing the emission pattern of which type of electromagnetic radiation? a. How is the direction of propagation of an electromagnetic wave oriented relative to the associated E and B fields? a. parallel to both E and B b. An ultraviolet light has a wavelength of 300 nm and speed of 2.3 10-6 s b.3 102 Hz b. perpendicular to E EM61. 1. 10 1014 Hz EM60.7 1014 Hz EM59.033 10-6 s EM58. Microwave radiation is useful in which of the following? a.1 108 m/s through a transparent medium. What is the frequency of this wave in the medium? (1 nm = 10-9 m and c = 3 108 m/s) a. perpendicular to B d. All of the above are valid choices EM62. microwave b. 6. perpendicular to both E and B c. sending phone messages b.8 108 Hz b. 1. parallel to B. The human eye is sensitive to light with wavelength down to 390 nm.7 10-6 s c. 8. What is the frequency of radiation at this wavelength? (1 nm = 10-9 m and c = 3 108 m/s) a. infrared . cooking food c. 7. parallel to E. 7 1014 Hz d. absorption b. 3. changing magnetic fields produce electrical fields.9 10-4 mH EM65. changing electrical fields produce magnetic fields. resonance c. moving electrical charges produce magnetic fields.6 10-2 mH c. He added his own original hypothesis that: a. size of oven compartment c.8 10-3 mH d. b. Microwave ovens emit a frequency intended to be in resonance with which of the following? a. gamma c. ultraviolet EM64. 3.8 mH b. ultraviolet d. visible light d. d. infrared b.c. c. Of the various types of electromagnetic radiation. frequency of food molecules EM66. electrical charges produce electrical fields. which is the most penetrating through all forms of matter? a. reflection d. What value of inductance should be used in a series circuit with a capacitor of 1. 1. EM68. 2. refraction EM67. X-rays EM63. The phenomenon used by police radar is which of the following? a.8 10-3 microFarads when designed to radiate a wavelength of 35 m? (c = 3 108 m/s) a. frequency of water molecule b. frequency of metal lining of oven d. Maxwell guessed that visible light was an electromagnetic wave because of its: . Maxwell developed his theory of electromagnetism by combining previous discoveries. amplifying the electromagnetic radiation. a. all of the above EM73. b. EM69. increasing both its energy and momentum. c. rarely passes through glass windows. d. c. wavelength. b. energy. 0. d. can produce cancer. convection. none of the above will increase its speed. Find the frequency of X-rays of wavelength 10-10 m. increasing its frequency.a. 9 km d. 3 m c. d. using film sensitive to invisible radiation. b. c. b. speed. As an electromagnetic wave travels through free space. EM72. visible light. EM71. EM70. b. c. 3 1018 Hz . An object that is giving off only infrared electromagnetic waves is giving off heat through: a.3 cm b. frequency. c. conduction. is absorbed by ozone. What is the wavelength of 100 MHz television EM-waves? a. d. illuminating the object with infrared light. A camera that takes infrared photographs in the dark takes these pictures by: a. The electromagnetic radiation that causes tanning: a. increasing its energy only. d. using infrared filters. radiation. 10 m EM74. its speed can be increased by: a. EM61. EM49. EM65. 4000 V/m d. 2000 V/m c. EM50. EM64.b. EM45. EM60. EM67. D B B A D C A B C A C D C B D B B D A C C 1 1 2 1 1 1 1 1 1 2 2 2 2 1 1 1 1 2 1 1 1 . What is the maximum value of the electric field E at 1 meter from a 100-watt lightbulb radiating in all directions? (µ0 = 4π 10-7 T-m/A) a. EM47. EM54. 6 109 Hz d. 1000 V/m b. EM66. EM58. 3 1010 MHz c. EM53. 3 108 HZ EM75. EM46. EM59. EM62. EM44. EM48. 6000 V/m Chapter 22 (EM) EM41. EM42. EM63. EM75. EM72. EM70. EM69. C D C A D B A D 1 1 1 1 1 1 1 2 . EM71. EM74.EM68. EM73.