Solution Manual For Electrical Wiring
Residential 21st Edition by Ray C. Mullin,
Phil Simmons, Derek Vigstol Chapter 1-33
Electrical Wiring Residential – Original Practice Exam
Question 1
What is the primary purpose of the National Electrical Code (NEC)?
A. To reduce construction costs
B. To establish minimum electrical safety standards
C. To increase electrical consumption
D. To regulate utility rates
Answer: B. To establish minimum electrical safety standards
Rationale: The NEC provides minimum requirements for safe electrical installations to protect
people and property from electrical hazards.
Question 2
Which instrument is used to measure voltage?
A. Ammeter
B. Ohmmeter
C. Voltmeter
D. Wattmeter
Answer: C. Voltmeter
Rationale: A voltmeter measures electrical potential difference between two points in a circuit.
,Question 3
According to Ohm's Law, voltage equals:
A. Current × Resistance
B. Current ÷ Resistance
C. Resistance ÷ Current
D. Power × Current
Answer: A. Current × Resistance
Rationale: Ohm's Law states V = I × R.
Question 4
The unit of electrical resistance is:
A. Volt
B. Ampere
C. Watt
D. Ohm
Answer: D. Ohm
Rationale: Resistance is measured in ohms (Ω).
Question 5
A circuit breaker primarily protects against:
A. Low voltage
B. Overcurrent conditions
C. Moisture
D. Corrosion
Answer: B. Overcurrent conditions
Rationale: Circuit breakers open the circuit when current exceeds safe limits.
Question 6
,The grounding conductor is primarily intended to:
A. Increase voltage
B. Carry normal load current
C. Provide a safe fault-current path
D. Reduce wire size
Answer: C. Provide a safe fault-current path
Rationale: Grounding helps clear faults quickly and reduces shock hazards.
Question 7
A 15-amp branch circuit typically requires a minimum conductor size of:
A. 14 AWG copper
B. 12 AWG copper
C. 10 AWG copper
D. 8 AWG copper
Answer: A. 14 AWG copper
Rationale: NEC commonly permits 14 AWG copper conductors on 15-amp circuits.
Question 8
A GFCI is designed to protect against:
A. Short circuits only
B. Electric shock from ground faults
C. Overheating motors
D. Low voltage
Answer: B. Electric shock from ground faults
Rationale: Ground-Fault Circuit Interrupters detect current imbalance and quickly disconnect
power.
Question 9
, What does AFCI stand for?
A. Arc-Fault Circuit Interrupter
B. Alternating Fault Circuit Indicator
C. Automatic Fuse Circuit Installation
D. Arc Frequency Control Interface
Answer: A. Arc-Fault Circuit Interrupter
Rationale: AFCIs protect against electrical fires caused by arcing faults.
Question 10
Electrical power is measured in:
A. Volts
B. Amperes
C. Watts
D. Ohms
Answer: C. Watts
Rationale: Power equals voltage multiplied by current (P = V × I).
Question 11
What color insulation is commonly used for grounded (neutral) conductors?
A. Black
B. Red
C. White or gray
D. Green
Answer: C. White or gray
Rationale: NEC identifies grounded conductors with white or gray insulation.
Question 12
What color insulation is commonly used for equipment grounding conductors?
Residential 21st Edition by Ray C. Mullin,
Phil Simmons, Derek Vigstol Chapter 1-33
Electrical Wiring Residential – Original Practice Exam
Question 1
What is the primary purpose of the National Electrical Code (NEC)?
A. To reduce construction costs
B. To establish minimum electrical safety standards
C. To increase electrical consumption
D. To regulate utility rates
Answer: B. To establish minimum electrical safety standards
Rationale: The NEC provides minimum requirements for safe electrical installations to protect
people and property from electrical hazards.
Question 2
Which instrument is used to measure voltage?
A. Ammeter
B. Ohmmeter
C. Voltmeter
D. Wattmeter
Answer: C. Voltmeter
Rationale: A voltmeter measures electrical potential difference between two points in a circuit.
,Question 3
According to Ohm's Law, voltage equals:
A. Current × Resistance
B. Current ÷ Resistance
C. Resistance ÷ Current
D. Power × Current
Answer: A. Current × Resistance
Rationale: Ohm's Law states V = I × R.
Question 4
The unit of electrical resistance is:
A. Volt
B. Ampere
C. Watt
D. Ohm
Answer: D. Ohm
Rationale: Resistance is measured in ohms (Ω).
Question 5
A circuit breaker primarily protects against:
A. Low voltage
B. Overcurrent conditions
C. Moisture
D. Corrosion
Answer: B. Overcurrent conditions
Rationale: Circuit breakers open the circuit when current exceeds safe limits.
Question 6
,The grounding conductor is primarily intended to:
A. Increase voltage
B. Carry normal load current
C. Provide a safe fault-current path
D. Reduce wire size
Answer: C. Provide a safe fault-current path
Rationale: Grounding helps clear faults quickly and reduces shock hazards.
Question 7
A 15-amp branch circuit typically requires a minimum conductor size of:
A. 14 AWG copper
B. 12 AWG copper
C. 10 AWG copper
D. 8 AWG copper
Answer: A. 14 AWG copper
Rationale: NEC commonly permits 14 AWG copper conductors on 15-amp circuits.
Question 8
A GFCI is designed to protect against:
A. Short circuits only
B. Electric shock from ground faults
C. Overheating motors
D. Low voltage
Answer: B. Electric shock from ground faults
Rationale: Ground-Fault Circuit Interrupters detect current imbalance and quickly disconnect
power.
Question 9
, What does AFCI stand for?
A. Arc-Fault Circuit Interrupter
B. Alternating Fault Circuit Indicator
C. Automatic Fuse Circuit Installation
D. Arc Frequency Control Interface
Answer: A. Arc-Fault Circuit Interrupter
Rationale: AFCIs protect against electrical fires caused by arcing faults.
Question 10
Electrical power is measured in:
A. Volts
B. Amperes
C. Watts
D. Ohms
Answer: C. Watts
Rationale: Power equals voltage multiplied by current (P = V × I).
Question 11
What color insulation is commonly used for grounded (neutral) conductors?
A. Black
B. Red
C. White or gray
D. Green
Answer: C. White or gray
Rationale: NEC identifies grounded conductors with white or gray insulation.
Question 12
What color insulation is commonly used for equipment grounding conductors?
