MASSACHUSETTS ELECTRICIAN MASTER EXAM
QUESTIONS AND CORRECT ANSWERS (VERIFIED
ANSWERS) Q&A 2026 |INSTANT DOWNLOAD PDF
1. What is the primary purpose of grounding in an electrical
system?
A. To increase voltage
B. To reduce resistance
C. To provide a safe path for fault current
D. To improve lighting efficiency
Rationale: Grounding protects people and equipment by
directing fault current safely to earth, preventing electric shock
and fire hazards.
Correct Answer: C
2. According to the NEC, what is the minimum working space
depth in front of electrical equipment operating at 0–150 volts
to ground?
A. 24 inches
B. 30 inches
C. 36 inches
D. 42 inches
Rationale: NEC 110.26 requires at least 36 inches of clear
working space depending on conditions.
Correct Answer: C
,3. What device protects a circuit primarily from overcurrent
conditions?
A. Transformer
B. Circuit breaker
C. Relay
D. Capacitor
Rationale: Circuit breakers automatically open the circuit when
excessive current flows, preventing overheating and damage.
Correct Answer: B
4. What does Ohm’s Law state?
A. Voltage equals power times current
B. Voltage equals current times resistance
C. Current equals resistance divided by voltage
D. Resistance equals voltage times current
Rationale: Ohm’s Law formula is V = I × R.
Correct Answer: B
5. In a three-phase system, what is the phase difference
between each phase?
A. 60°
B. 90°
C. 120°
D. 180°
,Rationale: Three-phase power systems are separated by 120
degrees electrically.
Correct Answer: C
6. What is the main function of a transformer?
A. Store electricity
B. Convert AC to DC
C. Change voltage levels
D. Increase resistance
Rationale: Transformers step voltage up or down through
electromagnetic induction.
Correct Answer: C
7. According to NEC, what color is typically used for
equipment grounding conductors?
A. White
B. Green
C. Black
D. Red
Rationale: NEC requires equipment grounding conductors to be
green or bare copper.
Correct Answer: B
, 8. What type of current reverses direction periodically?
A. Direct current
B. Alternating current
C. Static current
D. Pulsed current
Rationale: Alternating current (AC) changes direction in cycles.
Correct Answer: B
9. Which instrument measures electrical resistance?
A. Voltmeter
B. Ammeter
C. Ohmmeter
D. Wattmeter
Rationale: An ohmmeter measures resistance in ohms.
Correct Answer: C
10. What NEC article covers grounding and bonding?
A. Article 210
B. Article 250
C. Article 300
D. Article 430
Rationale: NEC Article 250 governs grounding and bonding
requirements.
Correct Answer: B
QUESTIONS AND CORRECT ANSWERS (VERIFIED
ANSWERS) Q&A 2026 |INSTANT DOWNLOAD PDF
1. What is the primary purpose of grounding in an electrical
system?
A. To increase voltage
B. To reduce resistance
C. To provide a safe path for fault current
D. To improve lighting efficiency
Rationale: Grounding protects people and equipment by
directing fault current safely to earth, preventing electric shock
and fire hazards.
Correct Answer: C
2. According to the NEC, what is the minimum working space
depth in front of electrical equipment operating at 0–150 volts
to ground?
A. 24 inches
B. 30 inches
C. 36 inches
D. 42 inches
Rationale: NEC 110.26 requires at least 36 inches of clear
working space depending on conditions.
Correct Answer: C
,3. What device protects a circuit primarily from overcurrent
conditions?
A. Transformer
B. Circuit breaker
C. Relay
D. Capacitor
Rationale: Circuit breakers automatically open the circuit when
excessive current flows, preventing overheating and damage.
Correct Answer: B
4. What does Ohm’s Law state?
A. Voltage equals power times current
B. Voltage equals current times resistance
C. Current equals resistance divided by voltage
D. Resistance equals voltage times current
Rationale: Ohm’s Law formula is V = I × R.
Correct Answer: B
5. In a three-phase system, what is the phase difference
between each phase?
A. 60°
B. 90°
C. 120°
D. 180°
,Rationale: Three-phase power systems are separated by 120
degrees electrically.
Correct Answer: C
6. What is the main function of a transformer?
A. Store electricity
B. Convert AC to DC
C. Change voltage levels
D. Increase resistance
Rationale: Transformers step voltage up or down through
electromagnetic induction.
Correct Answer: C
7. According to NEC, what color is typically used for
equipment grounding conductors?
A. White
B. Green
C. Black
D. Red
Rationale: NEC requires equipment grounding conductors to be
green or bare copper.
Correct Answer: B
, 8. What type of current reverses direction periodically?
A. Direct current
B. Alternating current
C. Static current
D. Pulsed current
Rationale: Alternating current (AC) changes direction in cycles.
Correct Answer: B
9. Which instrument measures electrical resistance?
A. Voltmeter
B. Ammeter
C. Ohmmeter
D. Wattmeter
Rationale: An ohmmeter measures resistance in ohms.
Correct Answer: C
10. What NEC article covers grounding and bonding?
A. Article 210
B. Article 250
C. Article 300
D. Article 430
Rationale: NEC Article 250 governs grounding and bonding
requirements.
Correct Answer: B
