Limited Electrical Journeyperson Exam:
Verified Questions and Answers | Instant PDF
Study Guide
1.What is the unit used to measure electrical resistance?
A. Volt
B. Ampere
C. Watt
D. Ohm
Rationale: The ohm (Ω) is the standard unit of electrical
resistance. Resistance represents the opposition a material or
component provides to the flow of electric current.
2. According to Ohm's Law, which formula is used to calculate
current?
A. I = R × E
B. I = E ÷ R
C. I = E × R
D. I = R ÷ E
Rationale: Ohm's Law states that current (I) equals voltage (E)
divided by resistance (R). For example, a 120-volt circuit with 20
ohms of resistance has a current of 6 amperes.
3. A 120-volt load draws 10 amperes. How much power does
the load consume?
,A. 12 watts
B. 120 watts
C. 1,200 watts
D. 12,000 watts
Rationale: Electrical power in a single-phase resistive circuit can
be calculated using P = E × I. Therefore, 120 V × 10 A = 1,200 W.
4. What happens to current in a circuit when resistance
increases while voltage remains constant?
A. Current increases
B. Voltage increases
C. Current decreases
D. Power factor becomes unity
Rationale: Ohm's Law states I = E/R. With voltage held constant,
increasing resistance causes current to decrease.
5. Which instrument is normally used to measure electrical
current?
A. Ohmmeter
B. Voltmeter
C. Ammeter
D. Megohmmeter
Rationale: An ammeter measures current in amperes. A
voltmeter measures voltage, while an ohmmeter measures
resistance.
, 6. How should an ammeter normally be connected when
measuring current in a circuit?
A. In parallel with the load
B. Across the power source
C. In series with the circuit
D. Between neutral and grounding electrode
Rationale: Current must flow through an ammeter so that the
meter can measure it. Therefore, a conventional ammeter is
connected in series with the circuit.
7. What is the primary purpose of a fuse or circuit breaker?
A. Increase circuit voltage
B. Improve power factor
C. Reduce conductor resistance
D. Protect conductors from excessive current
Rationale: Overcurrent protective devices interrupt excessive
current before conductors are damaged by overheating. Their
primary function is protection against overcurrent conditions.
8. A circuit has a resistance of 24 ohms and is supplied by 120
volts. What is the current?
A. 2 amperes
B. 5 amperes
C. 24 amperes
D. 2,880 amperes
, Rationale: Using I = E/R, the current is 120 ÷ 24 = 5 amperes.
9. What is the primary purpose of an equipment grounding
conductor?
A. Carry normal neutral current
B. Increase circuit voltage
C. Provide a low-impedance path for fault current
D. Reduce the operating temperature of a load
Rationale: An equipment grounding conductor provides a
conductive path for fault current so that the overcurrent
protective device can operate quickly and disconnect the faulty
circuit.
10. Which type of current periodically reverses direction?
A. Direct current
B. Alternating current
C. Static current
D. Leakage current
Rationale: Alternating current reverses direction periodically.
Direct current generally flows in one direction.
Questions 11–20: Conductors, Wiring, and Circuit Installation
11. What is the main purpose of electrical insulation on a
conductor?
Verified Questions and Answers | Instant PDF
Study Guide
1.What is the unit used to measure electrical resistance?
A. Volt
B. Ampere
C. Watt
D. Ohm
Rationale: The ohm (Ω) is the standard unit of electrical
resistance. Resistance represents the opposition a material or
component provides to the flow of electric current.
2. According to Ohm's Law, which formula is used to calculate
current?
A. I = R × E
B. I = E ÷ R
C. I = E × R
D. I = R ÷ E
Rationale: Ohm's Law states that current (I) equals voltage (E)
divided by resistance (R). For example, a 120-volt circuit with 20
ohms of resistance has a current of 6 amperes.
3. A 120-volt load draws 10 amperes. How much power does
the load consume?
,A. 12 watts
B. 120 watts
C. 1,200 watts
D. 12,000 watts
Rationale: Electrical power in a single-phase resistive circuit can
be calculated using P = E × I. Therefore, 120 V × 10 A = 1,200 W.
4. What happens to current in a circuit when resistance
increases while voltage remains constant?
A. Current increases
B. Voltage increases
C. Current decreases
D. Power factor becomes unity
Rationale: Ohm's Law states I = E/R. With voltage held constant,
increasing resistance causes current to decrease.
5. Which instrument is normally used to measure electrical
current?
A. Ohmmeter
B. Voltmeter
C. Ammeter
D. Megohmmeter
Rationale: An ammeter measures current in amperes. A
voltmeter measures voltage, while an ohmmeter measures
resistance.
, 6. How should an ammeter normally be connected when
measuring current in a circuit?
A. In parallel with the load
B. Across the power source
C. In series with the circuit
D. Between neutral and grounding electrode
Rationale: Current must flow through an ammeter so that the
meter can measure it. Therefore, a conventional ammeter is
connected in series with the circuit.
7. What is the primary purpose of a fuse or circuit breaker?
A. Increase circuit voltage
B. Improve power factor
C. Reduce conductor resistance
D. Protect conductors from excessive current
Rationale: Overcurrent protective devices interrupt excessive
current before conductors are damaged by overheating. Their
primary function is protection against overcurrent conditions.
8. A circuit has a resistance of 24 ohms and is supplied by 120
volts. What is the current?
A. 2 amperes
B. 5 amperes
C. 24 amperes
D. 2,880 amperes
, Rationale: Using I = E/R, the current is 120 ÷ 24 = 5 amperes.
9. What is the primary purpose of an equipment grounding
conductor?
A. Carry normal neutral current
B. Increase circuit voltage
C. Provide a low-impedance path for fault current
D. Reduce the operating temperature of a load
Rationale: An equipment grounding conductor provides a
conductive path for fault current so that the overcurrent
protective device can operate quickly and disconnect the faulty
circuit.
10. Which type of current periodically reverses direction?
A. Direct current
B. Alternating current
C. Static current
D. Leakage current
Rationale: Alternating current reverses direction periodically.
Direct current generally flows in one direction.
Questions 11–20: Conductors, Wiring, and Circuit Installation
11. What is the main purpose of electrical insulation on a
conductor?
