Master Electrician Licensure Exam Practice
Test Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
(All subjects: Electrical Theory, Code, Safety, Design, and Estimating)
1. What is the primary purpose of the National Electrical Code (NEC)?
A. To increase the cost of electrical installations
B. To safeguard people and property from electrical hazards
C. To promote electrical energy efficiency
D. To provide local building standards
Rationale: The NEC’s primary goal is safety—protecting people and
property from electrical hazards.
,2. What is the standard voltage for residential lighting circuits in the
United States?
A. 480V
B. 277V
C. 120V
D. 208V
Rationale: Most residential lighting and receptacle circuits use 120 volts as
standard.
3. Which color is typically used for the grounded conductor in an electrical
system?
A. Green
B. White
C. Red
D. Black
Rationale: The NEC designates white or gray for grounded (neutral)
conductors.
4. What type of current changes direction periodically?
A. Direct current
B. Alternating current
C. Static current
D. Pulsed DC
,Rationale: Alternating current (AC) periodically reverses direction, unlike
DC.
5. Ohm’s Law states that current is equal to voltage divided by what?
A. Power
B. Capacitance
C. Resistance
D. Frequency
Rationale: Ohm’s Law: I = V / R, where current equals voltage divided by
resistance.
6. What is the function of a circuit breaker?
A. Increase voltage
B. Reduce current
C. Protect a circuit from overloads and short circuits
D. Control frequency
Rationale: Circuit breakers automatically disconnect power to protect
circuits from damage.
7. Which wire color is used for equipment grounding conductors?
A. Green or bare copper
B. Red
, C. White
D. Blue
Rationale: Green or bare conductors are always used for grounding
purposes.
8. What is the formula for electrical power?
A. P = I / R
B. P = V / I
C. P = V × I
D. P = V² / R
Rationale: Power equals voltage times current (P = VI).
9. What is the minimum size copper grounding electrode conductor for a
200-amp service?
A. No. 6 AWG
B. No. 4 AWG
C. No. 8 AWG
D. No. 10 AWG
Rationale: The NEC Table 250.66 specifies a No. 4 AWG copper grounding
conductor for 200A.
Test Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
(All subjects: Electrical Theory, Code, Safety, Design, and Estimating)
1. What is the primary purpose of the National Electrical Code (NEC)?
A. To increase the cost of electrical installations
B. To safeguard people and property from electrical hazards
C. To promote electrical energy efficiency
D. To provide local building standards
Rationale: The NEC’s primary goal is safety—protecting people and
property from electrical hazards.
,2. What is the standard voltage for residential lighting circuits in the
United States?
A. 480V
B. 277V
C. 120V
D. 208V
Rationale: Most residential lighting and receptacle circuits use 120 volts as
standard.
3. Which color is typically used for the grounded conductor in an electrical
system?
A. Green
B. White
C. Red
D. Black
Rationale: The NEC designates white or gray for grounded (neutral)
conductors.
4. What type of current changes direction periodically?
A. Direct current
B. Alternating current
C. Static current
D. Pulsed DC
,Rationale: Alternating current (AC) periodically reverses direction, unlike
DC.
5. Ohm’s Law states that current is equal to voltage divided by what?
A. Power
B. Capacitance
C. Resistance
D. Frequency
Rationale: Ohm’s Law: I = V / R, where current equals voltage divided by
resistance.
6. What is the function of a circuit breaker?
A. Increase voltage
B. Reduce current
C. Protect a circuit from overloads and short circuits
D. Control frequency
Rationale: Circuit breakers automatically disconnect power to protect
circuits from damage.
7. Which wire color is used for equipment grounding conductors?
A. Green or bare copper
B. Red
, C. White
D. Blue
Rationale: Green or bare conductors are always used for grounding
purposes.
8. What is the formula for electrical power?
A. P = I / R
B. P = V / I
C. P = V × I
D. P = V² / R
Rationale: Power equals voltage times current (P = VI).
9. What is the minimum size copper grounding electrode conductor for a
200-amp service?
A. No. 6 AWG
B. No. 4 AWG
C. No. 8 AWG
D. No. 10 AWG
Rationale: The NEC Table 250.66 specifies a No. 4 AWG copper grounding
conductor for 200A.
