ame: Exam 3--PHYS 102--S11 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. A concave spherical mirror has a radius of curvature of 20.0 cm. If the object is located at 20 cm, what is the magnification? a. -½ d. -1 b. 2 e. there is no image c. ¼ 2. A bank uses a mirror for security purposes. A person stands 10 m in front of the mirror, and the image is 6.7 m behind the mirror. What is the focal length of this mirror? a. -20 m d. 6.7 m b. -2 m e. 10 m c. 200 m 3. A convex lens has a focal length of 20 cm. The object is located 10 cm to the left of the lens. Which of these describes the image? a. virtual, upright, and to the right of the d. real, inverted, and to the right of the lens lens b. real, inverted, and to the left of the lens e. virtual, upright, and to the left of the lens c. virtual, inverted, and to the left of the lens 1
4. Consider the following two-lens system. What is the magnification of the final image? a. -2 c. 1 b. 2 d. 1/2 5. This figure shows a mirror along with the object and the image the mirror forms. What kind of mirror has produced this image? a. convex c. flat b. concave d. either convex or concave, depending on the object distance 2
6. What is the magnification of a flat mirror? a. 1/2 d. 1 b. -1 e. it depends on the object distance c. 2 7. Most cameras have an aperture to block the outer edges of the lens. What is the purpose of this aperture? a. to eliminate chromatic aberration c. to reduce the effects of spherical aberration b. to protect the film from cosmic rays d. to reduce the amount of harmful UV radiation from entering your eye 8. Which of these physical phenomena are the cause of a mirage? a. diffraction c. refraction b. reflection d. interference 9. Two slits are separated by a distance of 5.00 mm. Light of wavelength 522 nm is incident on the 2 slits. On a screen 12.2 meters away, what is the distance from the central maximum to the 3rd bright fringe? a. 1.91 mm d. 7.64 mm b. 3.82 mm e. 1.22 mm c. 0.0179 mm 10. A diffraction grating has 12000 lines/cm. Light of wavelength 436 nm is incident on the grating. How many bright spots are on the screen? a. 3 c. 2 b. 5 d. 1 3
11. The green line of gaseous mercury at 546 nm falls on a single-slit apparatus. If the fourth dark fringe is at 0.092 from the center-line, what is the slit width? a. 1.4 mm c. 2.8 mm b. 3.2 mm d. 1.0 mm 12. Consider these two waves. What type of interference occurs when the two waves combine? a. just partial destructive interference c. constructive interference b. no interference d. destructive interference 13. In the previous figure, by what amount are the two waves out of phase? a. 1 λ c. 0λ b. ¼ λ d. ½ λ 14. LIGO is an observatory that is based on which of these devices? a. an interferometer d. a photomultiplier tube b. a telescope e. a microscope c. a bolometer 15. In a double-slit experiment, when the wavelength of the light is increased, the interference pattern... a. disappears c. shrinks together b. spreads out d. stays the same 4
16. In a single-slit experiment, what path difference have the waves from each slit traveled to give a minimum at the indicated position? a. ½ λ c. 1½ λ b. 0λ d. 1 λ 17. Waves from a radio station with a wavelength of 600 m arrive at a home receiver a distance 50 km away from the transmitter by two paths. One is a direct-line path (the grey line in this figure) and the second by reflection from a mountain directly behind the receiver (the black line). What is the minimum distance between the mountain and receiver such that destructive interference occurs at the location of the listener? Assume no phase change on reflection. a. 450 m c. 300 m b. 150 m d. 600 m 5
18. Consider the superposition of these 2 waves. Which of the choices represents the interference pattern? a. c. b. d. 19. The melting point of water is 0º C. What is this in Kelvins? a. 273 K c. 0 K b. 32 K d. -273 K 6
20. You will use this table in the next two questions: A cylindrical steel sleeve is to be shrink-fitted over a steel shaft whose diameter is 3.2030 cm at 0.000 C. The diameter of the sleeve is 3.1860 cm at 0.000 C. To what temperature must the sleeve be heated before it will slip over the shaft? a. 485.1 ºC c. 1545 ºC b. 482.5 ºC d. 245.2 ºC 21. You have a copper rod that is stuck in a concrete block. Which of these is the best solution to remove the rod? a. heat the copper rod and the concrete block b. cool the copper rod and the concrete block c. heat the copper rod d. cool the concrete block 7
22. What is the equivalent of 70 ºF in Celsius? a. 70 ºC c. 34 ºC b. 42 ºC d. 21 ºC 23. A cylinder with a movable piston contains gas at a temperature of 296 K, a volume of 1.30 m 3, and an absolute pressure of 1.200x10 5 Pa. What will be its final temperature if the gas is compressed to 0.700 m 3 and the absolute pressure decreases to 0.800x10 5 Pa? a. 106 K c. 560 K b. 825 K d. 345 K 24. Two identical cylinders at the same pressure contain the same gas. If A contains three times as much gas as B, which cylinder has the higher temperature? a. Container A c. both have the same temperature b. Container B 25. The SI unit for temperature, the kelvin, is based, in part, on which of these physical quantities? a. the freezing point of water c. the temperature of water at which osctracism occurs b. the temperature of the triple point of water d. the pressure of water at which sublimation occurs 26. Which is the smallest unit of temperature: one degree Kelvin, Celsius, or Fahrenheit? a. Kelvin c. Kelvin & Celsius b. Fahrenheit d. Celsius 27. The correct answer for this question is A. a. A c. C b. B d. D 8
ID: A Exam 3--PHYS 102--S11 Answer Section MULTIPLE CHOICE 1. ANS: D PTS: 1 2. ANS: A PTS: 1 3. ANS: E PTS: 1 4. ANS: C PTS: 1 5. ANS: B PTS: 1 6. ANS: D PTS: 1 7. ANS: C PTS: 1 8. ANS: C PTS: 1 9. ANS: B PTS: 1 10. ANS: A PTS: 1 11. ANS: A PTS: 1 12. ANS: D PTS: 1 13. ANS: D PTS: 1 14. ANS: A PTS: 1 15. ANS: B PTS: 1 16. ANS: D PTS: 1 17. ANS: B PTS: 1 18. ANS: C PTS: 1 19. ANS: A PTS: 1 20. ANS: A PTS: 1 21. ANS: B PTS: 1 22. ANS: D PTS: 1 23. ANS: A PTS: 1 24. ANS: B PTS: 1 25. ANS: B PTS: 1 26. ANS: B PTS: 1 27. ANS: A PTS: 1 1