Latest LADWP Electrical Craft Helper Exam verified with correct answers
plus rationales 2026/2027 version
1. If a gear with 20 teeth drives a gear with 40 teeth, how does the driven gear rotate
compared with the driving gear?
A. In the same direction and twice as fast
B. In the opposite direction and half as fast
C. In the same direction and half as fast
D. In the opposite direction and twice as fast
Answer: B. In the opposite direction and half as fast.
Rationale: Two directly meshed gears rotate in opposite directions. The larger 40-tooth gear
turns at half the speed of the 20-tooth gear.
2. A 10-foot ladder is placed against a vertical wall. What is the safest general practice
before climbing?
A. Climb immediately
B. Inspect the ladder and ensure stable footing
C. Place it on loose material
D. Carry heavy tools while climbing
Answer: B. Inspect the ladder and ensure stable footing.
Rationale: Ladder inspection and stable placement are basic safety requirements before
climbing.
3. What does a voltmeter measure?
A. Current
B. Resistance only
C. Voltage
D. Mechanical force
Answer: C. Voltage.
Rationale: A voltmeter measures electrical potential difference, expressed in volts.
,4. What does an ammeter measure?
A. Current
B. Voltage
C. Resistance
D. Power factor only
Answer: A. Current.
Rationale: An ammeter measures electrical current, expressed in amperes.
5. Which instrument is commonly used to measure resistance?
A. Ohmmeter
B. Ammeter
C. Tachometer
D. Thermometer
Answer: A. Ohmmeter.
Rationale: Resistance is measured in ohms using an ohmmeter or the resistance function of a
multimeter.
6. 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. 20 A
Answer: C. 6 A.
Rationale: Ohm's law is I = V/R. Therefore, 120 ÷ 20 = 6 amperes.
7. If a circuit has 10 A of current and 12 V of voltage, what is its power?
A. 22 W
B. 120 W
C. 1.2 W
D. 1200 W
,Answer: B. 120 W.
Rationale: Electrical power can be calculated using P = V × I. Thus, 12 × 10 = 120 watts.
8. Which material is generally a good electrical conductor?
A. Copper
B. Rubber
C. Glass
D. Dry wood
Answer: A. Copper.
Rationale: Copper has high electrical conductivity and is widely used for electrical conductors.
9. What is the primary purpose of electrical insulation?
A. Increase current flow
B. Prevent unintended electrical contact
C. Increase conductor temperature
D. Reduce conductor size
Answer: B. Prevent unintended electrical contact.
Rationale: Insulation helps separate conductors from people, equipment, and other conductive
surfaces.
10. What should you do before using an unfamiliar electrical tool?
A. Use it immediately
B. Read the instructions and understand its safe operation
C. Remove its safety guard
D. Test it on yourself
Answer: B. Read the instructions and understand its safe operation.
Rationale: Understanding the correct operation and hazards of equipment reduces the risk of
injury and equipment damage.
, 11. Which tool is designed primarily for tightening or loosening nuts and bolts?
A. Wrench
B. Hacksaw
C. Pliers only
D. File
Answer: A. Wrench.
Rationale: Wrenches are designed to grip and turn nuts and bolts.
12. Which tool is commonly used to drive screws?
A. Screwdriver
B. Pipe wrench
C. Level
D. Tape measure
Answer: A. Screwdriver.
Rationale: Screwdrivers are designed to install and remove screws with matching drive types.
13. What is the primary purpose of a tape measure?
A. Measure distance or length
B. Test voltage
C. Cut wire
D. Detect current
Answer: A. Measure distance or length.
Rationale: A tape measure is a basic measuring tool used to determine dimensions and
distances.
14. A pulley system has a mechanical advantage. What does mechanical advantage allow?
A. A smaller input force can move a larger load, depending on the system
B. It eliminates gravity
C. It eliminates friction completely
D. It makes the load weightless
plus rationales 2026/2027 version
1. If a gear with 20 teeth drives a gear with 40 teeth, how does the driven gear rotate
compared with the driving gear?
A. In the same direction and twice as fast
B. In the opposite direction and half as fast
C. In the same direction and half as fast
D. In the opposite direction and twice as fast
Answer: B. In the opposite direction and half as fast.
Rationale: Two directly meshed gears rotate in opposite directions. The larger 40-tooth gear
turns at half the speed of the 20-tooth gear.
2. A 10-foot ladder is placed against a vertical wall. What is the safest general practice
before climbing?
A. Climb immediately
B. Inspect the ladder and ensure stable footing
C. Place it on loose material
D. Carry heavy tools while climbing
Answer: B. Inspect the ladder and ensure stable footing.
Rationale: Ladder inspection and stable placement are basic safety requirements before
climbing.
3. What does a voltmeter measure?
A. Current
B. Resistance only
C. Voltage
D. Mechanical force
Answer: C. Voltage.
Rationale: A voltmeter measures electrical potential difference, expressed in volts.
,4. What does an ammeter measure?
A. Current
B. Voltage
C. Resistance
D. Power factor only
Answer: A. Current.
Rationale: An ammeter measures electrical current, expressed in amperes.
5. Which instrument is commonly used to measure resistance?
A. Ohmmeter
B. Ammeter
C. Tachometer
D. Thermometer
Answer: A. Ohmmeter.
Rationale: Resistance is measured in ohms using an ohmmeter or the resistance function of a
multimeter.
6. 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. 20 A
Answer: C. 6 A.
Rationale: Ohm's law is I = V/R. Therefore, 120 ÷ 20 = 6 amperes.
7. If a circuit has 10 A of current and 12 V of voltage, what is its power?
A. 22 W
B. 120 W
C. 1.2 W
D. 1200 W
,Answer: B. 120 W.
Rationale: Electrical power can be calculated using P = V × I. Thus, 12 × 10 = 120 watts.
8. Which material is generally a good electrical conductor?
A. Copper
B. Rubber
C. Glass
D. Dry wood
Answer: A. Copper.
Rationale: Copper has high electrical conductivity and is widely used for electrical conductors.
9. What is the primary purpose of electrical insulation?
A. Increase current flow
B. Prevent unintended electrical contact
C. Increase conductor temperature
D. Reduce conductor size
Answer: B. Prevent unintended electrical contact.
Rationale: Insulation helps separate conductors from people, equipment, and other conductive
surfaces.
10. What should you do before using an unfamiliar electrical tool?
A. Use it immediately
B. Read the instructions and understand its safe operation
C. Remove its safety guard
D. Test it on yourself
Answer: B. Read the instructions and understand its safe operation.
Rationale: Understanding the correct operation and hazards of equipment reduces the risk of
injury and equipment damage.
, 11. Which tool is designed primarily for tightening or loosening nuts and bolts?
A. Wrench
B. Hacksaw
C. Pliers only
D. File
Answer: A. Wrench.
Rationale: Wrenches are designed to grip and turn nuts and bolts.
12. Which tool is commonly used to drive screws?
A. Screwdriver
B. Pipe wrench
C. Level
D. Tape measure
Answer: A. Screwdriver.
Rationale: Screwdrivers are designed to install and remove screws with matching drive types.
13. What is the primary purpose of a tape measure?
A. Measure distance or length
B. Test voltage
C. Cut wire
D. Detect current
Answer: A. Measure distance or length.
Rationale: A tape measure is a basic measuring tool used to determine dimensions and
distances.
14. A pulley system has a mechanical advantage. What does mechanical advantage allow?
A. A smaller input force can move a larger load, depending on the system
B. It eliminates gravity
C. It eliminates friction completely
D. It makes the load weightless
