PRACTICE EXAM QUESTIONS AND
CORRECT ANSWERS (VERIFIED
ANSWERS) PLUS RATIONALES 2026
Q&A | INSTANT DOWNLOAD PDF
1. What is the minimum burial depth for a direct-buried cable under a
residential driveway?
A. 12 inches
B. 18 inches
C. 24 inches
D. 30 inches
It must be buried at least 24 inches under residential driveways per NEC
Table 300.5.
2. The color white in an electrical circuit typically designates which type
of conductor?
A. Grounding
B. Neutral
C. Hot
D. Equipment bonding
White is the standard color for neutral conductors per NEC Article 200.
,3. What is the allowable ampacity of a #10 AWG copper conductor with
75°C insulation?
A. 25 amps
B. 30 amps
C. 35 amps
D. 40 amps
According to NEC Table 310.16, #10 AWG copper rated at 75°C has 35A
ampacity.
4. A 20-amp branch circuit supplying receptacles in a dwelling must use
what minimum size conductor?
A. 14 AWG
B. 12 AWG
C. 10 AWG
D. 8 AWG
Per NEC 210.19(A)(4), 20A circuits require 12 AWG minimum.
5. What is the maximum number of 12 AWG conductors allowed in a 4-
inch square box, 2-1/8 inches deep?
A. 7
B. 8
C. 9
D. 10
Using NEC Table 314.16(B), 4-inch box has 30.3 cubic inches / 2.5 cu in
per conductor = 9 conductors.
6. The voltage between two hot wires of a single-phase, 120/240V
system is:
, A. 120V
B. 240V
C. 208V
D. 480V
Two hot legs of a single-phase system are 180° out of phase, giving
240V.
7. Ground-fault circuit-interrupters (GFCIs) are required in which of the
following locations?
A. Bedrooms
B. Living rooms
C. Bathrooms
D. Hallways
NEC 210.8(A)(1) requires GFCIs in bathrooms.
8. What is the standard service voltage for most residential homes in
the United States?
A. 120V only
B. 120/240V single-phase
C. 240V three-phase
D. 208/120V
Typical homes receive single-phase 120/240V service.
9. What is the resistance of a 12-ohm resistor connected in parallel with
a 6-ohm resistor?
A. 4 ohms
B. 6 ohms
C. 4 ohms