CT Unlimited Electrical Journeyperson (E-2)
Exam Questions and Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf
1. What is the primary purpose of an overcurrent protective device
in an electrical circuit?
A. To increase circuit voltage
B. To improve power factor
C. To protect conductors and equipment from excessive current
D. To reduce electrical resistance
Rationale: Overcurrent protective devices such as fuses and circuit
breakers are designed to interrupt excessive current before it can
cause conductor overheating, insulation damage, equipment failure,
or fire.
2. What is the standard unit used to measure electrical current?
,A. Volt
B. Ohm
C. Watt
D. Ampere
Rationale: The ampere (amp) is the SI unit of electric current. Voltage
is measured in volts, resistance in ohms, and power in watts.
3. Which formula correctly expresses Ohm’s law?
A. P = VI
B. E = IR
C. P = I²R
D. R = P/I
Rationale: Ohm’s law states that voltage (E) equals current (I)
multiplied by resistance (R). This relationship is fundamental to
calculating circuit values.
4. A 120-volt circuit has a resistance of 20 ohms. Approximately how
much current flows through the circuit?
A. 2 A
B. 4 A
C. 6 A
D. 10 A
,Rationale: Using Ohm’s law, I = E/R = 120/20 = 6 amperes.
5. What is the main function of the grounded conductor in a typical
120/240-volt single-phase system?
A. To provide overcurrent protection
B. To serve only as a grounding electrode
C. To provide a return path for current in unbalanced loads
D. To increase available fault current
Rationale: The grounded conductor, commonly called the neutral,
carries the unbalanced current from line-to-neutral loads back to the
source in a typical split-phase system.
6. Which conductor is normally identified by white or gray
insulation?
A. Ungrounded conductor
B. Equipment grounding conductor
C. Grounded conductor
D. Switch leg only
Rationale: NEC identification rules generally require grounded circuit
conductors to be identified by white or gray insulation or marking,
subject to specific exceptions.
, 7. What is the primary purpose of an equipment grounding
conductor?
A. To carry normal neutral current
B. To reduce voltage drop
C. To provide a low-impedance path for fault current
D. To increase circuit resistance
Rationale: The equipment grounding conductor provides a conductive
path for fault current so the overcurrent protective device can operate
quickly and disconnect the faulty circuit.
8. Which material is most commonly used for electrical conductors
because of its high conductivity and relatively good mechanical
properties?
A. Steel
B. Aluminum oxide
C. Copper
D. PVC
Rationale: Copper has excellent electrical conductivity, flexibility, and
durability, making it a common conductor material for many electrical
installations.
9. What does the term “ampacity” mean?
Exam Questions and Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf
1. What is the primary purpose of an overcurrent protective device
in an electrical circuit?
A. To increase circuit voltage
B. To improve power factor
C. To protect conductors and equipment from excessive current
D. To reduce electrical resistance
Rationale: Overcurrent protective devices such as fuses and circuit
breakers are designed to interrupt excessive current before it can
cause conductor overheating, insulation damage, equipment failure,
or fire.
2. What is the standard unit used to measure electrical current?
,A. Volt
B. Ohm
C. Watt
D. Ampere
Rationale: The ampere (amp) is the SI unit of electric current. Voltage
is measured in volts, resistance in ohms, and power in watts.
3. Which formula correctly expresses Ohm’s law?
A. P = VI
B. E = IR
C. P = I²R
D. R = P/I
Rationale: Ohm’s law states that voltage (E) equals current (I)
multiplied by resistance (R). This relationship is fundamental to
calculating circuit values.
4. A 120-volt circuit has a resistance of 20 ohms. Approximately how
much current flows through the circuit?
A. 2 A
B. 4 A
C. 6 A
D. 10 A
,Rationale: Using Ohm’s law, I = E/R = 120/20 = 6 amperes.
5. What is the main function of the grounded conductor in a typical
120/240-volt single-phase system?
A. To provide overcurrent protection
B. To serve only as a grounding electrode
C. To provide a return path for current in unbalanced loads
D. To increase available fault current
Rationale: The grounded conductor, commonly called the neutral,
carries the unbalanced current from line-to-neutral loads back to the
source in a typical split-phase system.
6. Which conductor is normally identified by white or gray
insulation?
A. Ungrounded conductor
B. Equipment grounding conductor
C. Grounded conductor
D. Switch leg only
Rationale: NEC identification rules generally require grounded circuit
conductors to be identified by white or gray insulation or marking,
subject to specific exceptions.
, 7. What is the primary purpose of an equipment grounding
conductor?
A. To carry normal neutral current
B. To reduce voltage drop
C. To provide a low-impedance path for fault current
D. To increase circuit resistance
Rationale: The equipment grounding conductor provides a conductive
path for fault current so the overcurrent protective device can operate
quickly and disconnect the faulty circuit.
8. Which material is most commonly used for electrical conductors
because of its high conductivity and relatively good mechanical
properties?
A. Steel
B. Aluminum oxide
C. Copper
D. PVC
Rationale: Copper has excellent electrical conductivity, flexibility, and
durability, making it a common conductor material for many electrical
installations.
9. What does the term “ampacity” mean?
