LADWP ELECTRICAL HELPER 2026/2027 exam verified with correct answers plus
rationales 2026/2027 instant pdf
1. What is the primary purpose of a circuit breaker?
A. Increase voltage
B. Protect a circuit from excessive current
C. Store electrical energy
D. Increase resistance
Correct Answer: B
Rationale: A circuit breaker opens the circuit when excessive current flows, helping protect
conductors and equipment.
2. Which unit is used to measure electrical current?
A. Volt
B. Ohm
C. Ampere
D. Watt
Correct Answer: C
Rationale: Current is measured in amperes, commonly abbreviated as amps (A).
3. Which unit measures electrical resistance?
A. Ohm
B. Volt
C. Ampere
D. Watt
Correct Answer: A
Rationale: Resistance is measured in ohms (Ω).
4. According to Ohm's law, if voltage is 120 V and resistance is 20 Ω, what is the current?
,A. 2 A
B. 4 A
C. 6 A
D. 12 A
Correct Answer: C
Rationale: Ohm's law is I = V/R. Therefore, 120 ÷ 20 = 6 A.
5. What happens to current in a circuit if resistance increases while voltage remains
constant?
A. Current increases
B. Current decreases
C. Current remains exactly the same
D. Voltage becomes zero
Correct Answer: B
Rationale: According to Ohm's law, current is inversely related to resistance when voltage
remains constant.
6. What is electrical power measured in?
A. Watts
B. Ohms
C. Amperes
D. Coulombs
Correct Answer: A
Rationale: Electrical power is measured in watts (W).
7. A tool has a power rating of 1,200 W and operates at 120 V. Approximately how much
current does it draw?
A. 5 A
B. 10 A
C. 20 A
D. 120 A
,Correct Answer: B
Rationale: Using P = VI, current = 1,200 ÷ 120 = 10 A.
8. What is the safest assumption when approaching an electrical conductor whose
energized status is unknown?
A. It is safe because no sparks are visible
B. It is energized until properly verified otherwise
C. It is grounded automatically
D. It has no voltage if the insulation looks intact
Correct Answer: B
Rationale: Unknown electrical equipment or conductors should be treated as energized until
appropriate procedures establish that they are de-energized.
9. What is the primary purpose of personal protective equipment (PPE)?
A. Replace safe work procedures
B. Reduce exposure to workplace hazards
C. Increase electrical current
D. Make tools operate faster
Correct Answer: B
Rationale: PPE provides a layer of protection against identified hazards but does not replace
proper procedures, engineering controls, or training.
10. Before working on electrical equipment that can be de-energized, what is an important
safety step?
A. Assume someone else has disconnected it
B. Follow the required lockout/tagout and verification procedure
C. Touch the conductor to test it
D. Remove warning labels
Correct Answer: B
, Rationale: Lockout/tagout procedures help prevent unexpected energization. Proper verification
is also necessary before work begins.
11. What does a pulley primarily do?
A. Change or transmit the direction of a force
B. Measure electrical resistance
C. Generate voltage automatically
D. Increase wire insulation
Correct Answer: A
Rationale: Pulleys can redirect force and, depending on the arrangement, provide mechanical
advantage.
12. Two meshing gears rotate together. If the first gear rotates clockwise, in which
direction does the second gear rotate?
A. Clockwise
B. Counterclockwise
C. It does not rotate
D. It rotates randomly
Correct Answer: B
Rationale: Directly meshing gears rotate in opposite directions.
13. A small gear drives a larger gear. Compared with the small gear, the larger gear
generally rotates:
A. Faster
B. Slower
C. At exactly the same speed
D. Without torque
Correct Answer: B
Rationale: A larger driven gear rotates more slowly than a smaller driving gear, while providing
greater torque.
rationales 2026/2027 instant pdf
1. What is the primary purpose of a circuit breaker?
A. Increase voltage
B. Protect a circuit from excessive current
C. Store electrical energy
D. Increase resistance
Correct Answer: B
Rationale: A circuit breaker opens the circuit when excessive current flows, helping protect
conductors and equipment.
2. Which unit is used to measure electrical current?
A. Volt
B. Ohm
C. Ampere
D. Watt
Correct Answer: C
Rationale: Current is measured in amperes, commonly abbreviated as amps (A).
3. Which unit measures electrical resistance?
A. Ohm
B. Volt
C. Ampere
D. Watt
Correct Answer: A
Rationale: Resistance is measured in ohms (Ω).
4. According to Ohm's law, if voltage is 120 V and resistance is 20 Ω, what is the current?
,A. 2 A
B. 4 A
C. 6 A
D. 12 A
Correct Answer: C
Rationale: Ohm's law is I = V/R. Therefore, 120 ÷ 20 = 6 A.
5. What happens to current in a circuit if resistance increases while voltage remains
constant?
A. Current increases
B. Current decreases
C. Current remains exactly the same
D. Voltage becomes zero
Correct Answer: B
Rationale: According to Ohm's law, current is inversely related to resistance when voltage
remains constant.
6. What is electrical power measured in?
A. Watts
B. Ohms
C. Amperes
D. Coulombs
Correct Answer: A
Rationale: Electrical power is measured in watts (W).
7. A tool has a power rating of 1,200 W and operates at 120 V. Approximately how much
current does it draw?
A. 5 A
B. 10 A
C. 20 A
D. 120 A
,Correct Answer: B
Rationale: Using P = VI, current = 1,200 ÷ 120 = 10 A.
8. What is the safest assumption when approaching an electrical conductor whose
energized status is unknown?
A. It is safe because no sparks are visible
B. It is energized until properly verified otherwise
C. It is grounded automatically
D. It has no voltage if the insulation looks intact
Correct Answer: B
Rationale: Unknown electrical equipment or conductors should be treated as energized until
appropriate procedures establish that they are de-energized.
9. What is the primary purpose of personal protective equipment (PPE)?
A. Replace safe work procedures
B. Reduce exposure to workplace hazards
C. Increase electrical current
D. Make tools operate faster
Correct Answer: B
Rationale: PPE provides a layer of protection against identified hazards but does not replace
proper procedures, engineering controls, or training.
10. Before working on electrical equipment that can be de-energized, what is an important
safety step?
A. Assume someone else has disconnected it
B. Follow the required lockout/tagout and verification procedure
C. Touch the conductor to test it
D. Remove warning labels
Correct Answer: B
, Rationale: Lockout/tagout procedures help prevent unexpected energization. Proper verification
is also necessary before work begins.
11. What does a pulley primarily do?
A. Change or transmit the direction of a force
B. Measure electrical resistance
C. Generate voltage automatically
D. Increase wire insulation
Correct Answer: A
Rationale: Pulleys can redirect force and, depending on the arrangement, provide mechanical
advantage.
12. Two meshing gears rotate together. If the first gear rotates clockwise, in which
direction does the second gear rotate?
A. Clockwise
B. Counterclockwise
C. It does not rotate
D. It rotates randomly
Correct Answer: B
Rationale: Directly meshing gears rotate in opposite directions.
13. A small gear drives a larger gear. Compared with the small gear, the larger gear
generally rotates:
A. Faster
B. Slower
C. At exactly the same speed
D. Without torque
Correct Answer: B
Rationale: A larger driven gear rotates more slowly than a smaller driving gear, while providing
greater torque.
