New York City DCAS Electrician Civil Service Exam 2026 | Questions, Solutions & Explained Rationales Study Guide

New York City DCAS Electrician Civil Service
Exam 2026 | Questions, Solutions &
Explained Rationales Study Guide

NEW YORK CITY DCAS ELECTRICIAN CIVIL SERVICE EXAM 2026 Study Guide |
Questions, Solutions & Explained EXPERT RATIONALE



• This guide features five-option multiple-choice questions with bolded correct
answers and detailed EXPERT RATIONALE — covering every major topic on the
NYC DCAS Electrician Civil Service Exam, from NEC code and electrical theory to
motors, transformers, grounding, load calculations, and NYC-specific requirements.

• Study by attempting each question independently before checking the highlighted
correct answer, then read every EXPERT RATIONALE carefully — focus extra review
time on sections where you select wrong answers, and cycle back through those
questions until you achieve consistent accuracy.



1. What is the unit of electrical resistance?

A. Ampere

B. Volt

C. Watt

D. Ohm

E. Coulomb

✓ Correct Answer: D. Ohm

EXPERT RATIONALE: Electrical resistance is measured in Ohms (Ω), named after
Georg Simon Ohm. Ampere measures current, Volt measures potential difference,
Watt measures power, and Coulomb measures electric charge.



2. According to Ohm's Law, if voltage is 120V and resistance is 20Ω, what is the
current?

,A. 2,400 A

B. 100 A

C. 6 A

D. 0.6 A

E. 60 A

✓ Correct Answer: C. 6 A

EXPERT RATIONALE: Ohm's Law states I = V/R. Therefore I = 120V ÷ 20Ω = 6
Amperes.



3. What is the power consumed by a 10Ω resistor with 5A of current flowing
through it?

A. 50 W

B. 500 W

C. 250 W

D. 2 W

E. 25 W

✓ Correct Answer: C. 250 W

EXPERT RATIONALE: Power P = I²R = (5)² × 10 = 25 × 10 = 250 Watts.



4. In a series circuit, how does the total resistance relate to individual
resistances?

A. Total resistance equals the sum of all individual resistances

B. Total resistance equals the product of all individual resistances

C. Total resistance is less than the smallest resistance

D. Total resistance equals the average of all resistances

,E. Total resistance equals the largest individual resistance

✓ Correct Answer: A. Total resistance equals the sum of all individual
resistances

EXPERT RATIONALE: In a series circuit, R_total = R1 + R2 + R3 + ... The total
resistance is the arithmetic sum of all individual resistances in the circuit.



5. In a parallel circuit with two equal resistors of 10Ω each, what is the total
resistance?

A. 20 Ω

B. 10 Ω

C. 5 Ω

D. 2 Ω

E. 0.2 Ω

✓ Correct Answer: C. 5 Ω

EXPERT RATIONALE: For parallel resistors of equal value, R_total = R/n = 10/2 = 5Ω.
Alternatively, 1/R_total = 1/10 + 1/10 = 2/10, so R_total = 5Ω.



6. What is the standard frequency of AC power in the United States?

A. 50 Hz

B. 60 Hz

C. 25 Hz

D. 120 Hz

E. 400 Hz

✓ Correct Answer: B. 60 Hz

, EXPERT RATIONALE: Standard AC power in the United States operates at 60 Hertz
(cycles per second). Most of Europe and many other countries use 50 Hz.



7. A circuit has a voltage of 240V and draws 20A. What is the power in
kilowatts?

A. 12 kW

B. 4.8 kW

C. 480 kW

D. 2.4 kW

E. 48 kW

✓ Correct Answer: B. 4.8 kW

EXPERT RATIONALE: P = V × I = 240 × 20 = 4,800 W = 4.8 kW.



8. What does the term "EMF" stand for in electrical terminology?

A. Electromagnetic Field

B. Electrical Measuring Force

C. Electromotive Force

D. Electron Motion Factor

E. Energy Magnitude Factor

✓ Correct Answer: C. Electromotive Force

EXPERT RATIONALE: EMF stands for Electromotive Force — the energy per unit
charge that drives current through a circuit. It is measured in volts and is what a
battery or generator produces.