Massachusetts Master Electrician Examination
(License A) Practice Questions and Correct
Answers (Verified Answers) Plus Rationale
2027 Q&A| Instant Download Pdf
1. What is the primary purpose of a master electrician license in
Massachusetts?
A. To permit work only under direct supervision of a journeyman
B. To authorize the license holder to perform and supervise electrical
work within the scope of the license
C. To authorize plumbing and gas-fitting work
D. To eliminate the need for electrical permits
Answer: B. To authorize the license holder to perform and supervise
electrical work within the scope of the license
Rationale: A master electrician license represents an advanced level of
electrical qualification. A master electrician may perform electrical
work and exercise the responsibilities associated with supervising
,electrical installations within the authority granted by Massachusetts
law and regulations. It does not authorize unrelated trades or
eliminate permitting requirements.
2. Which component of an electrical circuit provides the intentional
path for current to return to the source under normal operation?
A. Equipment grounding conductor
B. Grounding electrode conductor
C. Grounded circuit conductor
D. Bonding jumper
Answer: C. Grounded circuit conductor
Rationale: The grounded circuit conductor, commonly called the
neutral in many systems, carries current back to the source during
normal operation. The equipment grounding conductor is intended
primarily for fault-current paths and normally does not carry load
current.
3. A 120-volt load draws 10 amperes. What is the approximate
power consumed by the load?
,A. 12 W
B. 120 W
C. 1,200 W
D. 12,000 W
Answer: C. 1,200 W
Rationale: For a single-phase resistive load, power is calculated as P =
E × I. Therefore, 120 volts × 10 amperes = 1,200 watts.
4. What is the main purpose of overcurrent protection?
A. To increase circuit voltage
B. To protect conductors and equipment from excessive current
C. To improve power factor
D. To eliminate voltage drop
Answer: B. To protect conductors and equipment from excessive
current
Rationale: Fuses and circuit breakers interrupt a circuit when current
exceeds the permitted level. Proper overcurrent protection helps
prevent conductor overheating, insulation damage, equipment
damage, and fire hazards.
, 5. Which formula is used to determine resistance when voltage and
current are known?
A. R = E × I
B. R = E ÷ I
C. R = I ÷ E
D. R = E + I
Answer: B. R = E ÷ I
Rationale: Ohm's law states E = I × R. Rearranging the equation gives
R = E ÷ I. For example, a 120-volt circuit carrying 10 amperes has a
resistance of 12 ohms.
6. What is the primary purpose of bonding normally non-current-
carrying metal parts of an electrical system?
A. To increase normal load current
B. To provide a low-impedance path for fault current
C. To reduce conductor ampacity
D. To increase circuit resistance
Answer: B. To provide a low-impedance path for fault current
Rationale: Bonding connects conductive parts together so that, during
a fault, sufficient current can travel back to the source to operate the
(License A) Practice Questions and Correct
Answers (Verified Answers) Plus Rationale
2027 Q&A| Instant Download Pdf
1. What is the primary purpose of a master electrician license in
Massachusetts?
A. To permit work only under direct supervision of a journeyman
B. To authorize the license holder to perform and supervise electrical
work within the scope of the license
C. To authorize plumbing and gas-fitting work
D. To eliminate the need for electrical permits
Answer: B. To authorize the license holder to perform and supervise
electrical work within the scope of the license
Rationale: A master electrician license represents an advanced level of
electrical qualification. A master electrician may perform electrical
work and exercise the responsibilities associated with supervising
,electrical installations within the authority granted by Massachusetts
law and regulations. It does not authorize unrelated trades or
eliminate permitting requirements.
2. Which component of an electrical circuit provides the intentional
path for current to return to the source under normal operation?
A. Equipment grounding conductor
B. Grounding electrode conductor
C. Grounded circuit conductor
D. Bonding jumper
Answer: C. Grounded circuit conductor
Rationale: The grounded circuit conductor, commonly called the
neutral in many systems, carries current back to the source during
normal operation. The equipment grounding conductor is intended
primarily for fault-current paths and normally does not carry load
current.
3. A 120-volt load draws 10 amperes. What is the approximate
power consumed by the load?
,A. 12 W
B. 120 W
C. 1,200 W
D. 12,000 W
Answer: C. 1,200 W
Rationale: For a single-phase resistive load, power is calculated as P =
E × I. Therefore, 120 volts × 10 amperes = 1,200 watts.
4. What is the main purpose of overcurrent protection?
A. To increase circuit voltage
B. To protect conductors and equipment from excessive current
C. To improve power factor
D. To eliminate voltage drop
Answer: B. To protect conductors and equipment from excessive
current
Rationale: Fuses and circuit breakers interrupt a circuit when current
exceeds the permitted level. Proper overcurrent protection helps
prevent conductor overheating, insulation damage, equipment
damage, and fire hazards.
, 5. Which formula is used to determine resistance when voltage and
current are known?
A. R = E × I
B. R = E ÷ I
C. R = I ÷ E
D. R = E + I
Answer: B. R = E ÷ I
Rationale: Ohm's law states E = I × R. Rearranging the equation gives
R = E ÷ I. For example, a 120-volt circuit carrying 10 amperes has a
resistance of 12 ohms.
6. What is the primary purpose of bonding normally non-current-
carrying metal parts of an electrical system?
A. To increase normal load current
B. To provide a low-impedance path for fault current
C. To reduce conductor ampacity
D. To increase circuit resistance
Answer: B. To provide a low-impedance path for fault current
Rationale: Bonding connects conductive parts together so that, during
a fault, sufficient current can travel back to the source to operate the
