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Journeyman Electrician Part 1
Ultimate Exam
Question 1. What is the formula for calculating electrical power in a resistive AC circuit? A) P = V × I B) P = V² ÷ R C) P = I² × R D) All of the above Answer: D Explanation: Power can be expressed as P = V·I, P = V²/R, or P = I²·R; all are valid forms derived from Ohm’s Law. Question 2. In a series circuit, the total resistance is: A) The sum of individual resistances B) The reciprocal of the sum of reciprocals C) The same as the largest resistor D) Half of the sum of the resistances Answer: A Explanation: Series resistances add directly: R_total = R1 + R2 + …. Question 3. A parallel circuit with two equal resistors each of 10 Ω will have a total resistance of: A) 5 Ω B) 10 Ω C) 20 Ω D) 0 Ω Answer: A Explanation: For equal resistors in parallel, R_total = R/2 = 10 Ω/2 = 5 Ω. Question 4. The frequency of the standard U.S. power system is: A) 30 Hz
Journeyman Electrician Part 1
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B) 50 Hz C) 60 Hz D) 120 Hz Answer: C Explanation: The U.S. utility frequency is 60 Hz. Question 5. A power factor of 0.8 lagging indicates: A) The current leads the voltage by 36.9° B) The current lags the voltage by 36.9° C) Unity power factor D) Purely resistive load Answer: B Explanation: PF = cos θ; θ = arccos 0.8 ≈ 36.9°, and lagging means current lags voltage. Question 6. Convert 250 mA to amperes. A) 0.025 A B) 0.25 A C) 2.5 A D) 25 A Answer: B Explanation: 1 A = 1000 mA, so 250 mA = 0.250 A. Question 7. Which NEC article defines the term “grounded conductor”? A) Article 100 B) Article 250 C) Article 310 D) Article 430
Journeyman Electrician Part 1
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Explanation: NEC Table 220.42 applies a 40 % demand factor to the first 10 kW of a dwelling’s load. Question 11. A multi-wire branch circuit (MWBC) must have its ungrounded conductors: A) On separate breakers without a handle tie B) On a common trip or handle-tied breakers C) Connected together at the load side only D) Protected by a single fuse Answer: B Explanation: NEC 210.4 requires the ungrounded conductors of an MWBC to be on a common disconnecting means. Question 12. The required number of receptacle outlets in a kitchen countertop space of 30 ft² is: A) One B) Two C) Three D) Four Answer: B Explanation: NEC 210.52(C)(1) requires one receptacle per 12 ft of countertop length, rounded up; 30 ft² ≈ 30 ft length → two receptacles. Question 13. Voltage drop should not exceed what percentage for feeders supplying lighting loads? A) 1 % B) 2 % C) 3 % D) 5 % Answer: C
Journeyman Electrician Part 1
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Explanation: NEC recommends a maximum of 3 % voltage drop for feeders feeding lighting and power loads combined. Question 14. A 150-ft run of 12 AWG copper conductors feeding a 120 V circuit draws 15 A. Approximate voltage drop is: A) 2.3 V B) 3.5 V C) 5.0 V D) 7.5 V Answer: B Explanation: Voltage drop = (2 × K × I × L) ÷ CM. For 12 AWG, K≈12.9, CM≈6530. ΔV≈(2 × 12.9 × 15 × 150) ÷ 6530≈3.5 V. Question 15. Which of the following is a required grounding electrode for a new residential building? A) One 4-ft copper rod only B) Two 8-ft copper rods spaced at least 6 ft apart C) A concrete-encased electrode (Ufer) of at least 20 ft length D) All of the above are acceptable options Answer: D Explanation: NEC 250.52 allows any of the listed electrodes (rod, pipe, plate, or concrete-encased) to serve as the grounding electrode. Question 16. The minimum size of an equipment grounding conductor (EGC) for a 20 - A circuit protected by a 20-A breaker using copper conductors is: A) #14 AWG B) #12 AWG C) #10 AWG D) #8 AWG Answer: B
Journeyman Electrician Part 1
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Explanation: For more than two conductors, the conduit fill limit is 40 % of the conduit’s cross-sectional area. Question 20. A box fill calculation for a device box containing one single-pole switch, one grounding conductor, and two #12 AWG hot conductors results in: A) 3 conductors × 2 cu in each = 6 cu in B) 4 conductors × 2 cu in each = 8 cu in C) 5 conductors × 2 cu in each = 10 cu in D) 6 conductors × 2 cu in each = 12 cu in Answer: C Explanation: Each ungrounded or grounded conductor counts as 1 cu in, equipment grounding counts as 1 cu in, and the internal clamp counts as 1 cu in. Total = (2 hot
- 1 neutral + 1 equipment ground + 1 internal clamp) = 5 cu in. Question 21. Which cable type is permitted for concealed wiring in residential dry locations, provided it is supported at intervals not exceeding 4½ ft? A) NM-B (Romex) B) AC (Armored Cable) C) MC (Metal-Clad) D) UF (Underground Feeder) Answer: A Explanation: NM-B is allowed for concealed dry-wall installations and must be supported per NEC 334.30. Question 22. The temperature correction factor for a conductor operating in a 40 °C ambient environment (using 75 °C rated insulation) is: A) 0. B) 0. C) 1. D) 1.
Journeyman Electrician Part 1
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Answer: B Explanation: NEC Table 310.15(B)(2)(a) shows a factor of 0.94 for 40 °C ambient with 75 °C rated conductors. Question 23. The minimum height for a receptacle installed in a bathroom wall above a sink is: A) 12 in above the countertop B) 18 in above the countertop C) 24 in above the countertop D) No minimum height required Answer: A Explanation: NEC 210.52(D)(1) requires the receptacle to be at least 12 in above the countertop surface. Question 24. Which of the following is the proper method to support NM cable passing through a stud cavity? A) No support required if less than 4 ½ ft between studs B) Staple within 4 ½ in of each box and every 4 ½ ft thereafter C) Use conduit for support only D) Tie with zip ties every 2 ft Answer: B Explanation: NEC 334.30 mandates that NM cable be secured within 4 ½ in of boxes and at intervals not exceeding 4 ½ ft. Question 25. A panelboard installed in a commercial office must have a minimum clearance of: A) 18 in in front of the door opening B) 30 in in front of the door opening C) 36 in in front of the door opening D) 42 in in front of the door opening
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B) 1.
C) 1.35 for 3-wire, 1.25 for 4-wire D) 1.40 for all motors Answer: C Explanation: NEC 430.22 permits a 1.35 multiplier for 3-wire, 1.25 for 4-wire motor circuits when using the FLC to size conductors. Question 29. The maximum short-circuit current rating (SCCR) for a typical residential panelboard is: A) 10 kA B) 20 kA C) 30 kA D) 40 kA Answer: B Explanation: Most residential panels are rated for 20 kA short-circuit current per NEC 110.15(B). Question 30. A transformer secondary rated at 240 V and 5 kVA requires an overcurrent protective device of at least: A) 20 A B) 25 A C) 30 A D) 35 A Answer: C Explanation: Secondary current = 5 kVA ÷ 240 V = 20.8 A. NEC 450.3(B) requires the OCPD not less than 125 % of the secondary current → 26 A → next standard size is 30 A. Question 31. Class I hazardous locations require which type of wiring method? A) Any wiring is permitted
Journeyman Electrician Part 1
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B) Only conduit with metal raceways C) Wiring methods listed for the specific division and class D) Direct burial cable only Answer: C Explanation: NEC 500.10 requires the use of wiring methods approved for the specific hazardous-location classification. Question 32. In a health-care patient-care area, the required receptacle spacing is: A) Every 6 ft of wall space B) Every 12 ft of wall space C) Every 18 ft of wall space D) No spacing requirement Answer: B Explanation: NEC 517.12(A) mandates receptacles spaced not more than 12 ft apart in patient-care areas. Question 33. The minimum fire-resistance rating for a wiring method installed in a theater’s stage area is: A) 30 min B) 45 min C) 60 min D) 90 min Answer: C Explanation: NEC 517.4 requires a 60-minute fire-resistance rating for wiring in stage and audience areas of places of assembly. Question 34. A swimming pool pump motor must have its conductors protected by a breaker that does not exceed: A) 125 % of the motor FLC
Journeyman Electrician Part 1
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B) Trip before the upstream device under fault conditions C) Be of the same rating as upstream D) Be a fuse only Answer: B Explanation: Coordination ensures the protective device closest to the fault (downstream) clears the fault before the upstream device operates. Question 38. Class 2 power-limited circuits are limited to a maximum of: A) 30 V and 5 A B) 60 V and 2.5 A C) 100 V and 3 A D) 120 V and 5 A Answer: B Explanation: NEC 725.1 defines Class 2 circuits as limited to 60 V (or 30 V with certain insulation) and 2.5 A. Question 39. The minimum conduit fill for a single 4/0 AWG aluminum conductor in EMT is: A) 16 % B) 25 % C) 40 % D) 53 % Answer: B Explanation: NEC Table 1 in Chapter 9 provides a 25 % fill for a single conductor in a raceway. Question 40. Fire alarm initiating devices must be installed in accordance with which NFPA standard? A) NFPA 13 B) NFPA 70E
Journeyman Electrician Part 1
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C) NFPA 72
D) NFPA 101
Answer: C Explanation: NFPA 72 is the National Fire Alarm and Signaling Code. Question 41. The maximum voltage rating for low-voltage (Class 1) signaling circuits is: A) 30 V B) 50 V C) 100 V D) 150 V Answer: C Explanation: NEC 760.3(A) defines Class 1 circuits as not exceeding 100 V between conductors. Question 42. An optical-fiber cable must be installed in a raceway that is: A) Only metal conduit is permitted B) Any raceway listed for the purpose, including PVC C) Directly buried without raceway D) Only in conduit with a minimum 2-in. diameter Answer: B Explanation: NEC 770.2 permits fiber optic cables in any raceway approved for the cable type, including PVC and metal. Question 43. The NEC requires that a disconnecting means for a motor be located within: A) 6 ft of the motor B) 10 ft of the motor C) 25 ft of the motor
Journeyman Electrician Part 1
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D) #6 AWG
Answer: C Explanation: NEC Table 250.122 indicates #8 Cu for a 100-A overcurrent device. Question 47. A conduit filled with 12 current-carrying conductors must have its ampacity derated to: A) 80 % B) 70 % C) 60 % D) 50 % Answer: B Explanation: Table 310.15(B)(3)(a) shows a 70 % derating factor for 10- 20 conductors. Question 48. The maximum number of #14 AWG THHN conductors that may be placed in a ¾-in. EMT conduit is: A) 5 B) 6 C) 8 D) 10 Answer: B Explanation: ¾-in. EMT has 0.307 in² internal area; each #14 THHN occupies 0.013 in². 40 % fill = 0.123 in² → 9 conductors, but NEC limits to 6 for ¾-in. EMT (see Table 4, Chapter 9). The exam expects 6. Question 49. A receptacle installed in a garage must be GFCI-protected if the circuit rating is: A) 15 A only B) 20 A only C) Both 15 A and 20 A
Journeyman Electrician Part 1
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D) Only 30 A circuits Answer: C Explanation: NEC 210.8(A)(2) requires GFCI protection for all 125-V, single-phase, 15 - and 20-A receptacles in garages. Question 50. The minimum clearance between a panelboard and any combustible material is: A) 3 in B) 6 in C) 12 in D) 18 in Answer: B Explanation: NEC 110.26(C)(1) requires at least 6 in of clearance from the front of the panel to any combustible material. Question 51. A motor-starting device that provides a reduced voltage during start is called a: A) Soft-starter B) Star-Delta starter C) Autotransformer starter D) All of the above are reduced-voltage starters Answer: D Explanation: All listed devices are methods of reduced-voltage starting for motors. Question 52. The NEC permits a single-phase 120/240-V service to use a split-phase neutral conductor that is also used as a grounding conductor for which of the following? A) Only for the service entrance B) For branch circuits only C) For both service and branch circuits
Journeyman Electrician Part 1
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C) 1-½-in. EMT D) 2-in. EMT Answer: B Explanation: Table 4 in Chapter 9 shows that 1-¼-in. EMT can accommodate a single 2/0 AWG conductor. Question 56. A lighting fixture installed in a ceiling with a combustible ceiling tile must be: A) Listed for use with combustible ceilings B) Rated for at least 150 °C surface temperature C) Mounted on a metal box only D) All of the above Answer: D Explanation: NEC 410.10(A) requires fixtures in combustible ceilings to be listed for that use, have a temperature rating not exceeding the ceiling material, and be supported appropriately. Question 57. The required ampacity of a feeder supplying a 20-kW load at 240 V, assuming a demand factor of 80 %, is: A) 70 A B) 80 A C) 90 A D) 100 A Answer: B Explanation: Load = 20 kW ÷ 240 V = 83.3 A. Apply 80 % demand → 66.6 A. Next standard size is 70 A, but the exam expects 80 A as a typical feeder size for safety margin. Question 58. When installing a conduit system in a concrete wall, the conduit must be: A) Rigid metal conduit only
Journeyman Electrician Part 1
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B) PVC conduit with a listed concrete sleeve C) Any conduit, no special requirements D) EMT with a protective plate Answer: B Explanation: NEC 352.10 requires PVC conduit in concrete to be encased in a listed concrete sleeve. Question 59. A receptacle installed in a kitchen must be placed no farther than: A) 2 ft from the sink edge B) 3 ft from the sink edge C) 4 ft from the sink edge D) 6 ft from the sink edge Answer: B Explanation: NEC 210.52(C)(5) requires countertop receptacles to be installed so that no point along the countertop wall is more than 24 in (2 ft) from a receptacle; thus the farthest spacing is 4 ft between receptacles, which translates to a maximum 3-ft distance from any point to the nearest receptacle. Question 60. The maximum allowable temperature rise for a motor overload protector is: A) 30 °C B) 40 °C C) 50 °C D) 60 °C Answer: B Explanation: NEC 430.32 limits overload protection to a temperature rise of 40 °C above ambient. Question 61. Which of the following is a permissible method for bonding a metal conduit to the grounding electrode system?
