Nevada C-2 Electrical Contractor
Exam Questions And Correct Answers
(Verified Answers) Plus Rationales
2026 Q&A | Instant Download Pdf
1. Which of the following is the primary purpose of grounding an
electrical system?
A. Increase voltage
B. Reduce current
C. Protect people and equipment from electrical faults
D. Increase resistance
Rationale: Grounding provides a path for electrical faults to safely
dissipate, reducing the risk of shock or equipment damage.
2. What is the standard voltage for a single-phase residential electrical
system in Nevada?
A. 120V
B. 120/240V
C. 208V
D. 277V
Rationale: Single-phase residential systems in the U.S., including Nevada,
typically use 120/240V for homes.
3. Which conductor color is typically used for grounding in residential
wiring?
A. Red
B. Black
C. Blue
D. Green or bare copper
,Rationale: Green or bare copper is the standard color for grounding
conductors to distinguish them from hot and neutral wires.
4. What is the maximum continuous load allowed on a 20-ampere
residential circuit breaker?
A. 12A
B. 15A
C. 16A
D. 20A
Rationale: NEC allows a continuous load to be 80% of the circuit rating.
20A x 0.8 = 16A.
5. Which device protects a circuit from overcurrent due to a short circuit
or overload?
A. Transformer
B. Circuit breaker
C. Capacitor
D. Grounding rod
Rationale: Circuit breakers are designed to interrupt the flow of electricity
during overloads or short circuits.
6. In a 3-phase, 4-wire system, the voltage between two phases of a 208V
system is:
A. 120V
B. 208V
C. 208V line-to-line
D. 240V
Rationale: In a 208V 3-phase system, 208V is measured between any two
phases.
7. Which NEC article covers wiring methods for residential dwellings?
A. Article 220
B. Article 300
C. Article 334
D. Article 430
, Rationale: Article 334 covers nonmetallic-sheathed cable (NM) used in
residential wiring.
8. What is the purpose of a GFCI (Ground-Fault Circuit Interrupter)?
A. Reduce voltage
B. Protect against electrical shock
C. Increase amperage
D. Convert AC to DC
Rationale: GFCIs detect ground faults and quickly interrupt the circuit to
prevent shock.
9. In electrical calculations, which formula is used to determine power in
watts?
A. V × R
B. V × I
C. I × R
D. V ÷ I
Rationale: Power (watts) = Voltage (V) × Current (I).
10. Which type of conduit is most resistant to corrosion for outdoor
installations?
A. PVC
B. EMT
C. Rigid Metal Conduit (RMC)
D. Flexible Metal Conduit
Rationale: Rigid metal conduit is highly durable and corrosion-resistant,
suitable for harsh outdoor environments.
11. What is the maximum distance a GFCI-protected receptacle can
be from a water source in a kitchen?
A. 2 feet
B. 4 feet
C. 6 feet
D. 8 feet
Exam Questions And Correct Answers
(Verified Answers) Plus Rationales
2026 Q&A | Instant Download Pdf
1. Which of the following is the primary purpose of grounding an
electrical system?
A. Increase voltage
B. Reduce current
C. Protect people and equipment from electrical faults
D. Increase resistance
Rationale: Grounding provides a path for electrical faults to safely
dissipate, reducing the risk of shock or equipment damage.
2. What is the standard voltage for a single-phase residential electrical
system in Nevada?
A. 120V
B. 120/240V
C. 208V
D. 277V
Rationale: Single-phase residential systems in the U.S., including Nevada,
typically use 120/240V for homes.
3. Which conductor color is typically used for grounding in residential
wiring?
A. Red
B. Black
C. Blue
D. Green or bare copper
,Rationale: Green or bare copper is the standard color for grounding
conductors to distinguish them from hot and neutral wires.
4. What is the maximum continuous load allowed on a 20-ampere
residential circuit breaker?
A. 12A
B. 15A
C. 16A
D. 20A
Rationale: NEC allows a continuous load to be 80% of the circuit rating.
20A x 0.8 = 16A.
5. Which device protects a circuit from overcurrent due to a short circuit
or overload?
A. Transformer
B. Circuit breaker
C. Capacitor
D. Grounding rod
Rationale: Circuit breakers are designed to interrupt the flow of electricity
during overloads or short circuits.
6. In a 3-phase, 4-wire system, the voltage between two phases of a 208V
system is:
A. 120V
B. 208V
C. 208V line-to-line
D. 240V
Rationale: In a 208V 3-phase system, 208V is measured between any two
phases.
7. Which NEC article covers wiring methods for residential dwellings?
A. Article 220
B. Article 300
C. Article 334
D. Article 430
, Rationale: Article 334 covers nonmetallic-sheathed cable (NM) used in
residential wiring.
8. What is the purpose of a GFCI (Ground-Fault Circuit Interrupter)?
A. Reduce voltage
B. Protect against electrical shock
C. Increase amperage
D. Convert AC to DC
Rationale: GFCIs detect ground faults and quickly interrupt the circuit to
prevent shock.
9. In electrical calculations, which formula is used to determine power in
watts?
A. V × R
B. V × I
C. I × R
D. V ÷ I
Rationale: Power (watts) = Voltage (V) × Current (I).
10. Which type of conduit is most resistant to corrosion for outdoor
installations?
A. PVC
B. EMT
C. Rigid Metal Conduit (RMC)
D. Flexible Metal Conduit
Rationale: Rigid metal conduit is highly durable and corrosion-resistant,
suitable for harsh outdoor environments.
11. What is the maximum distance a GFCI-protected receptacle can
be from a water source in a kitchen?
A. 2 feet
B. 4 feet
C. 6 feet
D. 8 feet
