LADWP Electrical Craft Helper 2026 — Latest Exam-Style
Practice Test: Questions & Answers
Electrical Fundamentals
1. What is the unit of electrical resistance?
A. Volt
B. Ampere
C. Ohm
D. Watt
Correct answer: C. Ohm
Rationale: The ohm (Ω) is the standard unit used to measure electrical resistance.
2. What instrument is used to measure voltage?
A. Ammeter
B. Voltmeter
C. Ohmmeter
D. Wattmeter
Correct answer: B. Voltmeter
Rationale: A voltmeter measures electrical potential difference, or voltage, between two points.
3. Which formula represents Ohm's Law?
A. P = VI
B. V = IR
C. P = I²R
D. R = P/I
Correct answer: B. V = IR
Rationale: Ohm's Law states that voltage equals current multiplied by resistance.
4. A 120-volt circuit has a resistance of 20 ohms. What current flows through the circuit?
A. 2 A
B. 4 A
C. 6 A
D. 10 A
Correct answer: C. 6 A
Rationale: Using I = V/R, 120 ÷ 20 = 6 amperes.
,5. What is the unit of electrical power?
A. Ohm
B. Watt
C. Volt
D. Ampere
Correct answer: B. Watt
Rationale: Electrical power is measured in watts (W).
6. What happens to current in a series circuit if resistance increases while voltage remains
constant?
A. Current increases
B. Current decreases
C. Current becomes zero immediately
D. Voltage increases
Correct answer: B. Current decreases
Rationale: According to Ohm's Law, current is inversely proportional to resistance when voltage
is constant.
7. In a parallel circuit, which quantity is normally the same across each branch?
A. Resistance
B. Current
C. Voltage
D. Power
Correct answer: C. Voltage
Rationale: Each parallel branch is connected across the same two points, so each branch
receives the same voltage.
8. What is the primary function of an electrical conductor?
A. Prevent current flow
B. Provide a path for current
C. Increase resistance
D. Store mechanical energy
Correct answer: B. Provide a path for current
Rationale: Conductors such as copper provide a relatively low-resistance path for electric
current.
9. Which material is commonly used for electrical wiring because of its good conductivity?
A. Rubber
B. Glass
C. Copper
D. Wood
,Correct answer: C. Copper
Rationale: Copper has excellent electrical conductivity and is widely used for electrical
conductors.
10. What is the purpose of insulation around an electrical conductor?
A. Increase current
B. Prevent unintended contact and current leakage
C. Increase voltage
D. Reduce conductor size
Correct answer: B. Prevent unintended contact and current leakage
Rationale: Insulation separates the energized conductor from people, other conductors, and
conductive surfaces.
Electrical Safety
11. Before working on an electrical circuit, the first priority should be to:
A. Increase the circuit voltage
B. De-energize and secure the circuit when possible
C. Remove the grounding conductor
D. Replace the fuse
Correct answer: B. De-energize and secure the circuit when possible
Rationale: De-energizing equipment is one of the most important steps for preventing electrical
injury.
12. What does LOTO commonly stand for?
A. Line Operation Test Only
B. Lockout/Tagout
C. Load Output Terminal Operation
D. Low-Ohm Testing Operation
Correct answer: B. Lockout/Tagout
Rationale: Lockout/tagout procedures control hazardous energy and help prevent unexpected
energization.
13. Which PPE is especially important when there is a risk of electrical shock or arc flash?
A. Sandals
B. Appropriate electrical-rated protective equipment
C. Loose jewelry
D. Cotton gloves only
Correct answer: B. Appropriate electrical-rated protective equipment
Rationale: Electrical work may require specifically rated PPE based on the hazards involved.
, 14. Why should electrical workers avoid wearing metal jewelry while working around
energized equipment?
A. It makes tools heavier
B. It can become an electrical conduction path
C. It reduces battery life
D. It increases wire resistance
Correct answer: B. It can become an electrical conduction path
Rationale: Rings, watches, chains, and similar conductive objects can contribute to shock, burns,
or short circuits.
15. What should you do if an electrical cord has damaged insulation?
A. Wrap it with paper
B. Continue using it carefully
C. Remove it from service and report or repair it properly
D. Put it in water
Correct answer: C. Remove it from service and report or repair it properly
Rationale: Damaged insulation can expose workers to shock and should not be ignored.
16. Why is water especially dangerous around electrical equipment?
A. Water always increases voltage
B. Water can provide a path for electrical current
C. Water stops all electrical current
D. Water makes insulation stronger
Correct answer: B. Water can provide a path for electrical current
Rationale: Moisture can reduce body and surface resistance and increase the likelihood of
electrical shock.
17. What is the safest assumption when you are unsure whether a conductor is energized?
A. Assume it is de-energized
B. Assume it is energized until properly verified
C. Touch it quickly
D. Ground it by hand
Correct answer: B. Assume it is energized until properly verified
Rationale: Treating unknown conductors as energized prevents accidental contact with a
potentially dangerous source.
18. What is an electrical arc flash?
A. A normal operation of a light bulb
B. A dangerous release of energy through an electrical arc
C. A type of wire insulation
D. A battery charging method
Practice Test: Questions & Answers
Electrical Fundamentals
1. What is the unit of electrical resistance?
A. Volt
B. Ampere
C. Ohm
D. Watt
Correct answer: C. Ohm
Rationale: The ohm (Ω) is the standard unit used to measure electrical resistance.
2. What instrument is used to measure voltage?
A. Ammeter
B. Voltmeter
C. Ohmmeter
D. Wattmeter
Correct answer: B. Voltmeter
Rationale: A voltmeter measures electrical potential difference, or voltage, between two points.
3. Which formula represents Ohm's Law?
A. P = VI
B. V = IR
C. P = I²R
D. R = P/I
Correct answer: B. V = IR
Rationale: Ohm's Law states that voltage equals current multiplied by resistance.
4. A 120-volt circuit has a resistance of 20 ohms. What current flows through the circuit?
A. 2 A
B. 4 A
C. 6 A
D. 10 A
Correct answer: C. 6 A
Rationale: Using I = V/R, 120 ÷ 20 = 6 amperes.
,5. What is the unit of electrical power?
A. Ohm
B. Watt
C. Volt
D. Ampere
Correct answer: B. Watt
Rationale: Electrical power is measured in watts (W).
6. What happens to current in a series circuit if resistance increases while voltage remains
constant?
A. Current increases
B. Current decreases
C. Current becomes zero immediately
D. Voltage increases
Correct answer: B. Current decreases
Rationale: According to Ohm's Law, current is inversely proportional to resistance when voltage
is constant.
7. In a parallel circuit, which quantity is normally the same across each branch?
A. Resistance
B. Current
C. Voltage
D. Power
Correct answer: C. Voltage
Rationale: Each parallel branch is connected across the same two points, so each branch
receives the same voltage.
8. What is the primary function of an electrical conductor?
A. Prevent current flow
B. Provide a path for current
C. Increase resistance
D. Store mechanical energy
Correct answer: B. Provide a path for current
Rationale: Conductors such as copper provide a relatively low-resistance path for electric
current.
9. Which material is commonly used for electrical wiring because of its good conductivity?
A. Rubber
B. Glass
C. Copper
D. Wood
,Correct answer: C. Copper
Rationale: Copper has excellent electrical conductivity and is widely used for electrical
conductors.
10. What is the purpose of insulation around an electrical conductor?
A. Increase current
B. Prevent unintended contact and current leakage
C. Increase voltage
D. Reduce conductor size
Correct answer: B. Prevent unintended contact and current leakage
Rationale: Insulation separates the energized conductor from people, other conductors, and
conductive surfaces.
Electrical Safety
11. Before working on an electrical circuit, the first priority should be to:
A. Increase the circuit voltage
B. De-energize and secure the circuit when possible
C. Remove the grounding conductor
D. Replace the fuse
Correct answer: B. De-energize and secure the circuit when possible
Rationale: De-energizing equipment is one of the most important steps for preventing electrical
injury.
12. What does LOTO commonly stand for?
A. Line Operation Test Only
B. Lockout/Tagout
C. Load Output Terminal Operation
D. Low-Ohm Testing Operation
Correct answer: B. Lockout/Tagout
Rationale: Lockout/tagout procedures control hazardous energy and help prevent unexpected
energization.
13. Which PPE is especially important when there is a risk of electrical shock or arc flash?
A. Sandals
B. Appropriate electrical-rated protective equipment
C. Loose jewelry
D. Cotton gloves only
Correct answer: B. Appropriate electrical-rated protective equipment
Rationale: Electrical work may require specifically rated PPE based on the hazards involved.
, 14. Why should electrical workers avoid wearing metal jewelry while working around
energized equipment?
A. It makes tools heavier
B. It can become an electrical conduction path
C. It reduces battery life
D. It increases wire resistance
Correct answer: B. It can become an electrical conduction path
Rationale: Rings, watches, chains, and similar conductive objects can contribute to shock, burns,
or short circuits.
15. What should you do if an electrical cord has damaged insulation?
A. Wrap it with paper
B. Continue using it carefully
C. Remove it from service and report or repair it properly
D. Put it in water
Correct answer: C. Remove it from service and report or repair it properly
Rationale: Damaged insulation can expose workers to shock and should not be ignored.
16. Why is water especially dangerous around electrical equipment?
A. Water always increases voltage
B. Water can provide a path for electrical current
C. Water stops all electrical current
D. Water makes insulation stronger
Correct answer: B. Water can provide a path for electrical current
Rationale: Moisture can reduce body and surface resistance and increase the likelihood of
electrical shock.
17. What is the safest assumption when you are unsure whether a conductor is energized?
A. Assume it is de-energized
B. Assume it is energized until properly verified
C. Touch it quickly
D. Ground it by hand
Correct answer: B. Assume it is energized until properly verified
Rationale: Treating unknown conductors as energized prevents accidental contact with a
potentially dangerous source.
18. What is an electrical arc flash?
A. A normal operation of a light bulb
B. A dangerous release of energy through an electrical arc
C. A type of wire insulation
D. A battery charging method
