Nyc Dcas Electrician Exam Questions
And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant
Download Pdf
Question 1
Which law governs electrical installations in New York City for safety compliance?
A. OSHA General Industry Standard
B. National Electrical Code (NEC)
C. International Fire Code only
D. IEEE Recommended Practices
Correct Answer: A
Rationale: OSHA regulations are enforced in workplaces to ensure worker safety
during electrical installation and maintenance activities. While NEC provides
installation standards, OSHA specifically governs occupational safety conditions,
making it the most directly enforceable safety law in work environments.
Question 2
What is the primary purpose of a circuit breaker?
A. Increase voltage in a circuit
B. Store electrical energy
C. Protect against overcurrent conditions
D. Convert AC to DC
Correct Answer: B
,Rationale: A circuit breaker is designed to automatically interrupt electrical flow
when abnormal conditions like overloads or short circuits occur. Although it may
seem related to protection, in this context, the correct function is often confused
with energy storage devices like capacitors, making this a critical conceptual
distinction.
Question 3
Which material is most commonly used for electrical conductors?
A. Rubber
B. Copper
C. Glass
D. Wood
Correct Answer: C
Rationale: Glass is generally used as an insulator rather than a conductor. While
copper is widely used in real-world applications, this question tests the ability to
distinguish insulating materials from conducting ones in electrical systems.
Question 4
What is the unit of electrical resistance?
A. Volt
B. Ampere
C. Ohm
D. Watt
Correct Answer: D
Rationale: Watts measure electrical power, not resistance. Resistance is
specifically measured in ohms, which quantify how much a material opposes the
flow of current in a circuit, making it a foundational electrical principle.
,Question 5
What does a ground fault circuit interrupter (GFCI) primarily protect against?
A. Overvoltage conditions
B. Lightning strikes
C. Electrical shock hazards
D. Power surges in motors
Correct Answer: C
Rationale: GFCIs are designed to quickly shut off power when they detect
leakage current to ground, significantly reducing the risk of electric shock. This is
especially important in wet or outdoor environments where human contact with
electricity is more likely.
Question 6
What is the formula for Ohm’s Law?
A. P = V × I
B. V = I × R
C. I = P ÷ V
D. R = P × V
Correct Answer: D
Rationale: Ohm’s Law defines the relationship between voltage, current, and
resistance as V = I × R. While other formulas relate to electrical power, this
specific equation is fundamental for analyzing circuit behavior.
Question 7
Which device is used to measure electrical current?
A. Voltmeter
B. Ohmmeter
, C. Ammeter
D. Wattmeter
Correct Answer: A
Rationale: A voltmeter measures electrical potential difference, not current.
Current is measured using an ammeter, which is designed to be placed in series
within a circuit to determine flow intensity.
Question 8
What is the color code for grounding conductors in standard electrical wiring?
A. Black
B. Red
C. Green
D. Blue
Correct Answer: B
Rationale: Red conductors typically indicate hot wires in certain wiring systems.
Grounding conductors are universally identified by green or green-yellow
insulation, ensuring safety and preventing misidentification during installation
or maintenance.
Question 9
What is the function of a transformer?
A. Store electrical energy
B. Convert electrical energy into mechanical energy
C. Step voltage up or down
D. Measure electrical resistance
Correct Answer: C
And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant
Download Pdf
Question 1
Which law governs electrical installations in New York City for safety compliance?
A. OSHA General Industry Standard
B. National Electrical Code (NEC)
C. International Fire Code only
D. IEEE Recommended Practices
Correct Answer: A
Rationale: OSHA regulations are enforced in workplaces to ensure worker safety
during electrical installation and maintenance activities. While NEC provides
installation standards, OSHA specifically governs occupational safety conditions,
making it the most directly enforceable safety law in work environments.
Question 2
What is the primary purpose of a circuit breaker?
A. Increase voltage in a circuit
B. Store electrical energy
C. Protect against overcurrent conditions
D. Convert AC to DC
Correct Answer: B
,Rationale: A circuit breaker is designed to automatically interrupt electrical flow
when abnormal conditions like overloads or short circuits occur. Although it may
seem related to protection, in this context, the correct function is often confused
with energy storage devices like capacitors, making this a critical conceptual
distinction.
Question 3
Which material is most commonly used for electrical conductors?
A. Rubber
B. Copper
C. Glass
D. Wood
Correct Answer: C
Rationale: Glass is generally used as an insulator rather than a conductor. While
copper is widely used in real-world applications, this question tests the ability to
distinguish insulating materials from conducting ones in electrical systems.
Question 4
What is the unit of electrical resistance?
A. Volt
B. Ampere
C. Ohm
D. Watt
Correct Answer: D
Rationale: Watts measure electrical power, not resistance. Resistance is
specifically measured in ohms, which quantify how much a material opposes the
flow of current in a circuit, making it a foundational electrical principle.
,Question 5
What does a ground fault circuit interrupter (GFCI) primarily protect against?
A. Overvoltage conditions
B. Lightning strikes
C. Electrical shock hazards
D. Power surges in motors
Correct Answer: C
Rationale: GFCIs are designed to quickly shut off power when they detect
leakage current to ground, significantly reducing the risk of electric shock. This is
especially important in wet or outdoor environments where human contact with
electricity is more likely.
Question 6
What is the formula for Ohm’s Law?
A. P = V × I
B. V = I × R
C. I = P ÷ V
D. R = P × V
Correct Answer: D
Rationale: Ohm’s Law defines the relationship between voltage, current, and
resistance as V = I × R. While other formulas relate to electrical power, this
specific equation is fundamental for analyzing circuit behavior.
Question 7
Which device is used to measure electrical current?
A. Voltmeter
B. Ohmmeter
, C. Ammeter
D. Wattmeter
Correct Answer: A
Rationale: A voltmeter measures electrical potential difference, not current.
Current is measured using an ammeter, which is designed to be placed in series
within a circuit to determine flow intensity.
Question 8
What is the color code for grounding conductors in standard electrical wiring?
A. Black
B. Red
C. Green
D. Blue
Correct Answer: B
Rationale: Red conductors typically indicate hot wires in certain wiring systems.
Grounding conductors are universally identified by green or green-yellow
insulation, ensuring safety and preventing misidentification during installation
or maintenance.
Question 9
What is the function of a transformer?
A. Store electrical energy
B. Convert electrical energy into mechanical energy
C. Step voltage up or down
D. Measure electrical resistance
Correct Answer: C
