Maryland Master Electrician Exam
Practice Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. According to electrical theory, what is the current flowing through a
circuit with 240 volts applied across a 20-ohm resistance?
A. 8 A
B. 12 A
C. 14 A
D. 20 A
Rationale: Ohm’s Law states that current equals voltage divided by
resistance. Dividing 240 volts by 20 ohms results in 12 amperes.
2. Which NEC concept primarily protects conductors from excessive
heating due to overloads and short circuits?
A. Bonding jumpers
B. Disconnecting means
C. Overcurrent protection
D. Receptacle ratings
Rationale: Overcurrent protective devices such as fuses and circuit breakers
are designed to prevent conductor damage from excessive current.
, 3. What is the primary purpose of grounding electrical systems?
A. Increase voltage
B. Reduce conductor size
C. Improve power factor
D. Limit voltage imposed by lightning and faults
Rationale: Grounding stabilizes system voltage and helps safely dissipate
fault currents and lightning-induced surges.
4. A 120-volt circuit supplies a 1,440-watt load. What is the current
demand?
A. 10 A
B. 12 A
C. 14 A
D. 16 A
Rationale: Current equals power divided by voltage. Dividing 1,440 watts
by 120 volts yields 12 amperes.
5. Which conductor is intentionally connected to earth at the service
equipment?
A. Equipment grounding conductor
B. Bonding jumper
C. Grounding electrode conductor
D. Grounded conductor (neutral)
Rationale: The grounded conductor is intentionally connected to earth and
serves as the system neutral conductor.
6. What is the minimum ampacity requirement for a continuous load of
80 amperes?
, A. 80 A
B. 90 A
C. 100 A
D. 110 A
Rationale: Continuous loads must generally be calculated at 125% of the
load. Multiplying 80 by 1.25 equals 100 amperes.
7. Which NEC chapter primarily covers wiring methods and materials?
A. Chapter 1
B. Chapter 2
C. Chapter 3
D. Chapter 5
Rationale: Chapter 3 contains requirements for wiring methods, raceways,
conductors, and associated materials.
8. What device is designed to interrupt a circuit when a ground fault
occurs?
A. AFCI
B. GFCI
C. Disconnect switch
D. Transformer
Rationale: Ground-Fault Circuit Interrupters detect leakage current and
disconnect power rapidly to reduce shock hazards.
9. Which raceway system provides the greatest protection against
physical damage in most installations?
A. ENT
B. PVC Schedule 40
C. Flexible metal conduit
D. Rigid metal conduit
Practice Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. According to electrical theory, what is the current flowing through a
circuit with 240 volts applied across a 20-ohm resistance?
A. 8 A
B. 12 A
C. 14 A
D. 20 A
Rationale: Ohm’s Law states that current equals voltage divided by
resistance. Dividing 240 volts by 20 ohms results in 12 amperes.
2. Which NEC concept primarily protects conductors from excessive
heating due to overloads and short circuits?
A. Bonding jumpers
B. Disconnecting means
C. Overcurrent protection
D. Receptacle ratings
Rationale: Overcurrent protective devices such as fuses and circuit breakers
are designed to prevent conductor damage from excessive current.
, 3. What is the primary purpose of grounding electrical systems?
A. Increase voltage
B. Reduce conductor size
C. Improve power factor
D. Limit voltage imposed by lightning and faults
Rationale: Grounding stabilizes system voltage and helps safely dissipate
fault currents and lightning-induced surges.
4. A 120-volt circuit supplies a 1,440-watt load. What is the current
demand?
A. 10 A
B. 12 A
C. 14 A
D. 16 A
Rationale: Current equals power divided by voltage. Dividing 1,440 watts
by 120 volts yields 12 amperes.
5. Which conductor is intentionally connected to earth at the service
equipment?
A. Equipment grounding conductor
B. Bonding jumper
C. Grounding electrode conductor
D. Grounded conductor (neutral)
Rationale: The grounded conductor is intentionally connected to earth and
serves as the system neutral conductor.
6. What is the minimum ampacity requirement for a continuous load of
80 amperes?
, A. 80 A
B. 90 A
C. 100 A
D. 110 A
Rationale: Continuous loads must generally be calculated at 125% of the
load. Multiplying 80 by 1.25 equals 100 amperes.
7. Which NEC chapter primarily covers wiring methods and materials?
A. Chapter 1
B. Chapter 2
C. Chapter 3
D. Chapter 5
Rationale: Chapter 3 contains requirements for wiring methods, raceways,
conductors, and associated materials.
8. What device is designed to interrupt a circuit when a ground fault
occurs?
A. AFCI
B. GFCI
C. Disconnect switch
D. Transformer
Rationale: Ground-Fault Circuit Interrupters detect leakage current and
disconnect power rapidly to reduce shock hazards.
9. Which raceway system provides the greatest protection against
physical damage in most installations?
A. ENT
B. PVC Schedule 40
C. Flexible metal conduit
D. Rigid metal conduit
