EXAM COMPLETE PRACTICE EXAM
Here is a 320question complete practice exam for the Wyoming Master
Electrician license. These questions are based on the National Electrical Code
(NEC), electrical theory, and the types of calculations and code applications
you will encounter on the actual exam. Each question includes the correct
answer and a detailed rationale.
GENERAL KNOWLEDGE & ELECTRICAL THEORY (Questions 1–40)
1. Which law relates voltage, current, and resistance in an electrical circuit?
A. Faraday's Law
B. Ohm's Law
C. Kirchhoff's Voltage Law
D. Ampere's Law
Correct Answer: B
Rationale: Ohm's Law states that V = I × R, where voltage (V) is the product of
current (I) and resistance (R). This is a fundamental relationship in electrical
theory.
2. What is the term for the maximum current an electrical conductor can carry
without exceeding its temperature rating?
A. Voltage drop
,B. Ampacity
C. Resistance
D. Power factor
Correct Answer: B
Rationale: Ampacity is defined as the maximum current, in amperes, that a
conductor can carry continuously under the conditions of use without
exceeding its temperature rating.
3. Which fundamental electrical quantity is measured in volts?
A. Resistance
B. Voltage
C. Current
D. Power
Correct Answer: B
Rationale: Voltage is the electrical potential difference between two points
and is measured in volts.
4. What is the formula for calculating power in a DC circuit?
A. P = I × R
B. P = V × I
C. P = V / R
D. P = I² / R
Correct Answer: B
Rationale: Power (P) in a DC circuit is calculated as voltage (V) multiplied by
current (I). This is known as the power formula.
,5. Which of the following increases resistance in a conductor?
A. Lower temperature
B. Larger crosssection
C. Higher temperature
D. Copper material
Correct Answer: C
Rationale: Resistance increases as temperature rises in most conductors.
Higher temperature causes more atomic vibrations, which impede electron
flow.
6. What is the primary function of a relay?
A. Convert AC to DC
B. Provide electrical isolation and switching
C. Store charge
D. Reduce resistance
Correct Answer: B
Rationale: Relays allow low power control signals to switch higher power
circuits, providing electrical isolation between the control and load circuits.
7. Which equation correctly represents Ohm's Law?
A. P = V × I
B. V = I × R
C. I = V ÷ P
D. R = P ÷ I
Correct Answer: B
, Rationale: Ohm's Law states that voltage (V) equals current (I) multiplied by
resistance (R).
8. The term "ampacity" refers to:
A. The voltage drop in a conductor
B. The currentcarrying capacity of a conductor
C. The resistance of an electrical circuit
D. The power rating of a device
Correct Answer: B
Rationale: Ampacity is the maximum current an electrical conductor can carry
without exceeding its temperature rating.
9. In load calculations, which unit is used to measure power?
A. Volt
B. Ampere
C. Watt
D. Ohm
Correct Answer: C
Rationale: Power is measured in watts (W) and is calculated as voltage
multiplied by current.
10. What does NEC stand for in electrical installations?
A. National Energy Code
B. National Electrical Code
C. National Engineering Council
D. National Equipment Certification