IOWA MASTER ELECTRICIAN EXAM – COMPLETE
PRACTICE TEST BANK (2026-2027) 200+ QUESTIONS
WITH ANSWERS & DETAILED RATIONALES A+ VERIFIED
LATEST VERSION
1. Ohm’s Law states that:
A. Power equals voltage × current
B. Current equals voltage ÷ resistance
C. Voltage equals power ÷ current
D. Resistance equals current ÷ voltage
Answer: B
Rationale: Ohm’s Law is I = V ÷ R.
2. The unit of electrical power is:
A. Volt
B. Ampere
C. Watt
D. Ohm
Answer: C
Rationale: Power is measured in watts.
3. A 240V load drawing 10A consumes how many watts?
A. 240 W
B. 2400 W
C. 24 W
D. 24000 W
Answer: B
Rationale: P = V × I = 240 × 10 = 2400 W.
4. Resistance in a series circuit:
A. Decreases total resistance
B. Has no effect
C. Adds together
D. Becomes zero
,Answer: C
Rationale: Series resistances sum directly.
5. In parallel circuits, voltage across each branch is:
A. Divided
B. Equal
C. Added
D. Zero
Answer: B
Rationale: Voltage remains constant in parallel circuits.
6. The NEC is primarily concerned with:
A. Manufacturing standards
B. Electrical safety installation standards
C. Utility pricing
D. Appliance repair
Answer: B
Rationale: The NEC ensures safe electrical installation practices.
7. The grounding conductor is intended to:
A. Carry normal current
B. Provide a return path in normal operation
C. Carry fault current safely to earth
D. Increase voltage stability
Answer: C
Rationale: Grounding paths fault current safely.
8. What does a GFCI protect against?
A. Overvoltage
B. Short circuits
C. Ground faults
D. Lightning strikes
Answer: C
Rationale: GFCIs detect imbalance in current flow.
,9. Minimum working clearance in front of electrical equipment (NEC typical) is:
A. 1 foot
B. 2 feet
C. 3 feet
D. 6 feet
Answer: C
Rationale: NEC generally requires 3 feet of clearance.
10. A 14 AWG copper conductor is typically rated for:
A. 10A
B. 15A
C. 20A
D. 30A
Answer: B
Rationale: 14 AWG is commonly rated at 15 amps.
11. Conduit used for underground direct burial is commonly:
A. EMT
B. PVC Schedule 40/80
C. Flexible metal conduit
D. Rigid aluminum only
Answer: B
Rationale: PVC is corrosion-resistant and suitable for burial.
12. Voltage drop increases when:
A. Wire size increases
B. Distance decreases
C. Load current increases
D. Resistance decreases
Answer: C
Rationale: Higher current increases voltage drop.
13. Power factor is defined as:
A. Real power ÷ apparent power
B. Voltage ÷ current
, C. Resistance ÷ inductance
D. Current × voltage
Answer: A
Rationale: Power factor = real power / apparent power.
14. A fuse protects against:
A. Overcurrent
B. Grounding failure
C. Voltage spikes only
D. Frequency changes
Answer: A
Rationale: Fuses interrupt excessive current flow.
15. A circuit breaker trips due to:
A. High voltage only
B. Overcurrent condition
C. Low resistance
D. High frequency
Answer: B
Rationale: Breakers open under overload or short circuit.
16. NEC Article 250 covers:
A. Lighting systems
B. Grounding and bonding
C. Motors
D. Fire alarms
Answer: B
Rationale: Article 250 addresses grounding/bonding systems.
17. A series circuit has:
A. Multiple paths for current
B. One path for current
C. No resistance
D. Infinite current
PRACTICE TEST BANK (2026-2027) 200+ QUESTIONS
WITH ANSWERS & DETAILED RATIONALES A+ VERIFIED
LATEST VERSION
1. Ohm’s Law states that:
A. Power equals voltage × current
B. Current equals voltage ÷ resistance
C. Voltage equals power ÷ current
D. Resistance equals current ÷ voltage
Answer: B
Rationale: Ohm’s Law is I = V ÷ R.
2. The unit of electrical power is:
A. Volt
B. Ampere
C. Watt
D. Ohm
Answer: C
Rationale: Power is measured in watts.
3. A 240V load drawing 10A consumes how many watts?
A. 240 W
B. 2400 W
C. 24 W
D. 24000 W
Answer: B
Rationale: P = V × I = 240 × 10 = 2400 W.
4. Resistance in a series circuit:
A. Decreases total resistance
B. Has no effect
C. Adds together
D. Becomes zero
,Answer: C
Rationale: Series resistances sum directly.
5. In parallel circuits, voltage across each branch is:
A. Divided
B. Equal
C. Added
D. Zero
Answer: B
Rationale: Voltage remains constant in parallel circuits.
6. The NEC is primarily concerned with:
A. Manufacturing standards
B. Electrical safety installation standards
C. Utility pricing
D. Appliance repair
Answer: B
Rationale: The NEC ensures safe electrical installation practices.
7. The grounding conductor is intended to:
A. Carry normal current
B. Provide a return path in normal operation
C. Carry fault current safely to earth
D. Increase voltage stability
Answer: C
Rationale: Grounding paths fault current safely.
8. What does a GFCI protect against?
A. Overvoltage
B. Short circuits
C. Ground faults
D. Lightning strikes
Answer: C
Rationale: GFCIs detect imbalance in current flow.
,9. Minimum working clearance in front of electrical equipment (NEC typical) is:
A. 1 foot
B. 2 feet
C. 3 feet
D. 6 feet
Answer: C
Rationale: NEC generally requires 3 feet of clearance.
10. A 14 AWG copper conductor is typically rated for:
A. 10A
B. 15A
C. 20A
D. 30A
Answer: B
Rationale: 14 AWG is commonly rated at 15 amps.
11. Conduit used for underground direct burial is commonly:
A. EMT
B. PVC Schedule 40/80
C. Flexible metal conduit
D. Rigid aluminum only
Answer: B
Rationale: PVC is corrosion-resistant and suitable for burial.
12. Voltage drop increases when:
A. Wire size increases
B. Distance decreases
C. Load current increases
D. Resistance decreases
Answer: C
Rationale: Higher current increases voltage drop.
13. Power factor is defined as:
A. Real power ÷ apparent power
B. Voltage ÷ current
, C. Resistance ÷ inductance
D. Current × voltage
Answer: A
Rationale: Power factor = real power / apparent power.
14. A fuse protects against:
A. Overcurrent
B. Grounding failure
C. Voltage spikes only
D. Frequency changes
Answer: A
Rationale: Fuses interrupt excessive current flow.
15. A circuit breaker trips due to:
A. High voltage only
B. Overcurrent condition
C. Low resistance
D. High frequency
Answer: B
Rationale: Breakers open under overload or short circuit.
16. NEC Article 250 covers:
A. Lighting systems
B. Grounding and bonding
C. Motors
D. Fire alarms
Answer: B
Rationale: Article 250 addresses grounding/bonding systems.
17. A series circuit has:
A. Multiple paths for current
B. One path for current
C. No resistance
D. Infinite current
