2. The resistance to the flow of electrons in a material is measured in units called: a. amperes. b. ohms. c. volts. d. watts.

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1 As with the Chapter Review Tests and the Final Exam, the tests your understanding of the materials underlying the learning objectives. After you ve reviewed your answers to the Chapter Review Tests, try your hand at this 50-question to become still more comfortable with taking a multiple-choice test. Remember, topics covered in this exam may likewise be covered in the Final Exam, but the wording of the questions will never be identical.

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3 1. Luminous efficiency is measured by: a. color temperature in K. b. lumens per watt. c. watts per hour. d. footcandles per watt. 2. The resistance to the flow of electrons in a material is measured in units called: a. amperes. b. ohms. c. volts. d. watts. 3. When connecting an ammeter into a circuit, it must be connected: a. in series. b. in parallel. c. on the supply side. d. on the return side. 4. Generally, the most economical way to replace the fluorescent tubes in a building is to: a. replace them all at about 90% of rated lamp life. b. replace all in a fixture when one in that fixture burns out. c. replace each individual bulb as it burns out. d. replace them all at about 70% of rated lamp life. 5. The insulated grounding conductor should be color coded: a. green. b. blue. c. red. d. white. 6. (Fill in the blank) The building uses the most common type of multiphase power supply, which is -phase current. a. one b. two c. three d. four

4 7. When the peak positive current and voltage both occur at 90, the two sine waves are said to be: a. parallel. b. in sync. c. analogous. d. in phase. 8. A technician is working with a DC circuit that has a current of 0.5 A and a resistance of 20Ω. What is its voltage? a V b. 10V c. 40 V d. 100 V 9. As a transformer steps up voltage, all of the following characteristics will remain constant except: a. frequency. b. phase relationships. c. amperage. d. input and output power. 10. When working around wiring and electrical equipment, always assume that it is energized until it is confirmed otherwise by: a. an electrician. b. the equipment operator. c. your supervisor. d. your own test. 11. The amount of current flowing through R 1 in the diagram is: a..53 A. b. 48 A. c. 72 A. d. 1.2 A.

5 12. The total resistance of the circuit in the diagram is: a. 160 ohms. b. 46 ohms. c. 260 ohms. d. 106 ohms. 13. Boxes and enclosures should be installed at each of the following locations except: a. an outlet. b. a switch. c. a splice in wire. d. a 90 bend in wire. 14. Unbalanced voltage in three-phase induction motors can cause: a. motor overheating. b. damaging vibration. c. unnecessary friction. d. excessive current draw. 15. As there was a short circuit, the fuse blew. To make the circuit operational again, the technician must always replace: a. the element within the fuse, but not the fuse itself. b. the fuse itself, never just the element within the fuse. c. either the element within the fuse or the fuse itself. d. There is no established procedure for fuses. 16. In order to reduce imprecision associated with parallax, most analog meters use: a. numerical output. b. electronic circuits. c. more than one needle. d. a mirror behind the needle. 17. When checking the insulation resistance of critical motors, use a(n): a. multimeter. b. megger. c. ammeter. d. voltmeter.

6 18. Standard electric motors have an efficiency rate of approximately: a. 83%. b. 97%. c. 115%. d. 65%. 19. Single-line drawings are used to show power paths through: a. motors. b. pumps. c. main conductors. d. chillers. 20. The symbol depicted represents: a. conductors that are not connected. b. conductors, either connected or not, depending on conventions. c. a ground connection. d. conductors that are connected. 21. When it is possible to work on the circuit or equipment deenergized, do all of the following except: a. disconnect the circuit ground. b. switch the circuit off. c. lock the breaker out. d. put a tag on the breaker. 22. Except for motor circuits, the ampacity rating of the fuse, when compared to the ampacity rating of the circuit conductor, should always be: a. the same or lower. b. exactly the same. c. unrelated. d. the same or higher.

7 23. The National Electrical Code/Canadian Electrical Code (NEC/CEC) can carry the force of law when: a. determining liability for injury. b. referred to in the design specs. c. the rules contain the word shall. d. it is enacted by government. 24. The ampere rating at which the breaker can operate without exceeding its thermal limits is called the: a. current-limiting rating. b. continuous current rating. c. maximum current capacity. d. current-interrupting capacity. 25. Changing the normal 60 Hz line voltage supplied to an AC induction motor to another frequency varies all of the following except: a. the rotor speed. b. the slip percentage. c. the frequency phasing. d. the synchronous speed. 26. A separate grounding wire must be included when the conduit being used is: a. electrical metallic tubing. b. rigid metal conduit. c. plastic conduit. d. flexible metal conduit. 27. The electric current created when a conductor cuts through the lines of force of a magnetic field is called: a. flux. b. reactance. c. inductance. d. capacitance.

8 28. The process whereby the ampacity of a conductor is reduced because the conductor is enclosed in a raceway of conduit with many other conductors is called: a. blending. b. limiting. c. derating. d. combining. 29. The maximum load that a given motor can move is called: a. service factor. b. breakaway torque. c. load limit. d. breakdown torque. 30. The result of resistance, capacitive reactance, and inductive reactance is expressed as: a. degrees of phase displacement. b. reciprocance. c. electric resonance. d. impedance. 31. The NEC/CEC generally requires that all current-carrying conductors in a circuit be protected from damage by overcurrent at the point where: a. 15 or more amps of current may be required. b. equipment is connected to the circuit. c. three or more conductors converge. d. a conductor receives supply current. 32. Demand charges for a facility are based on: a. the difference between night and day consumption. b. how quickly power is consumed. c. the average amount of power consumed daily. d. comparisons with the surrounding community. 33. When compared to an identical new motor, the efficiency rating of a rewound motor is: a. higher or lower, depending on the job. b. higher by 1% to 5%. c. lower by 1% to 5%. d. the same.

9 34. The unit of light quantity or output is referred to as: a. lumen. b. candela. c. footcandle (lux). d. footlambert. 35. On split-phase and capacitor-start motors, when the motor reaches 75% of its normal operating speed: a. a capacitor releases additional current. b. a switch disconnects the starting winding. c. a circuit is activated that generates additional torque. d. the main winding is energized. 36. When a high degree of accuracy is not required, electrical technicians frequently check voltage with a: a. synchroscope. b. clamp-on multimeter. c. clamp-on ammeter. d. voltage tester. 37. You have been told that a motor is off. The first troubleshooting step is to: a. test the power source. b. perform a visual inspection. c. press the overload button. d. test the individual components. 38. When replacing fluorescent T-12 lamps with T-8 lamps, you must also replace the: a. fixtures. b. ballasts. c. starting circuit. d. electric service. 39. A motor might draw excessive current if the: a. motor is too close to a magnetic field. b. motor and equipment are out of alignment. c. the motor is operating at cold temperatures. d. motor pulley is too small.

10 40. The quickest way to locate overheating problems in an operating electrical device is to use a(n): a. circuit analyzer. b. infrared scanner. c. voltage tester. d. current tracer. 41. (Fill in the blank) A short circuit occurs when a fault in a circuit allows the current to the designed load or device. a. discontinue b. connect to c. complete the path for d. bypass 42. (Fill in the blanks) Electricity transmitted from the utility company typically is voltage and amperage. a. low; low b. low; high c. high; low d. high; high 43. When a wire is wrapped around a screw connection, it should be wrapped around the screw in: a. the direction required to tighten it. b. the direction required to loosen it. c. both directions if possible. d. either direction. 44. When using a multimeter, it is very dangerous for both you and the meter to test an energized AC circuit with the meter selector set to: a. DC volts. b. the off position. c. DC amps. d. ohms.

11 45. At the point where the conductor in a generator cuts through the maximum number of magnetic lines of force: a. flux increases. b. polarity reverses. c. voltage drops. d. peak voltage occurs. 46. The symbol depicted represents a(n): a. alternator. b. AC generator. c. DC generator. d. motor. 47. Electrical devices used to convert alternating current (AC) to direct current (DC) are called: a. converters. b. transformers. c. capacitors. d. rectifiers. 48. Two motors with the same frame number will be interchangeable: a. except for type of mounting and spacing of holes. b. in every dimension. c. except for distance from base to shaft. d. except for shaft diameter. 49. The maximum amount of conduit bending allowed by the NEC/CEC between enclosures is: a b. 90. c d The moving part of an AC motor is called the: a. alternator. b. stator. c. rotor. d. armature.

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13 Answers 1. B 2. B 3. A 4. D 5. A 6. C 7. D 8. B 9. C 10. D 11. D 12. B 13. D 14. A 15. C 16. D 17. B 18. A 19. C 20. A 21. A 22. A 23. D 24. B 25. C 26. C 27. C 28. C 29. D 30. D 31. D 32. B 33. C 34. A 35. B 36. D 37. B 38. B 39. B 40. B 41. D 42. C 43. A 44. D 45. D 46. D 47. D 48. B 49. D 50. C