LADWP ELECTRICAL HELPER TESTBANK 2026 –
300+ QUESTIONS, VERIFIED ANSWERS &
DETAILED RATIONALES
Topics Covered
Section
1 Electrical Fundamentals - Ohm's Law, circuits, resistance, conductors,
AC/DC theory
2 Knots, Bends & Hitches - Figure Eight, Bowline, Half-Hitch, Square Knot,
Sheet Bend, Carrick Bend
3 Hand & Power Tools - Identification, proper use, and safety precautions
4 Workplace Safety - OSHA standards, NFPA 70E, lockout/tagout, PPE
5 Materials & Construction - Conduit types, wiring methods, grounding,
installation practices
6 Mechanical Aptitude - Tools, mechanical advantage, basic physics
7 Mathematics -Arithmetic, algebra, geometry, electrical calculations
8 Situational Judgment - Decision-making, prioritization, interpersonal
skills
,SECTION 1: ELECTRICAL FUNDAMENTALS
Q1. What is the unit of electric resistance?
A) Volt
B) Ampere
C) Ohm
D) Watt
Answer: C
Rationale: Resistance is measured in ohms (Ω), defined by Ohm's Law as V = I × R. Volts
measure electromotive force, amperes measure current, and watts measure power.
Q2. Which material is the best conductor of electricity?
A) Aluminum
B) Copper
C) Steel
D) PVC
Answer: B
Rationale: Copper has the highest conductivity among common wiring materials, surpassing
aluminum and far exceeding non-conductors like steel or PVC.
,Q3. In a series circuit, if one component fails open, the entire circuit:
A) Continues to operate at reduced voltage
B) Remains fully functional
C) Loses all voltage across each component
D) Stops current flow completely
Answer: D
Rationale: An open in a series path breaks the single continuous loop, halting current flow
throughout the circuit. This is a fundamental characteristic of series circuits.
Q4. The standard frequency of AC power supplied in the United States is:
A) 25 Hz
B) 50 Hz
C) 60 Hz
D) 100 Hz
Answer: C
Rationale: U.S. utility grids operate at 60 hertz (Hz), whereas many other countries use 50 Hz.
Q5. Which of the following is the correct formula for Ohm's Law?
A) V = I / R
B) V = I × R
C) V = R / I
D) V = P × I
, Answer: B
Rationale: Ohm's Law states that voltage (V) equals current (I) multiplied by resistance (R): V =
I × R.
Q6. Which unit is used to measure electric current?
A) Ohm
B) Volt
C) Watt
D) Ampere
Answer: D
Rationale: Electric current is measured in amperes (A). Voltage is measured in volts, resistance
in ohms, and power in watts.
Q7. What does a voltmeter measure?
A) Electrical potential difference
B) Resistance
C) Current flow
D) Electrical power
Answer: A
Rationale: A voltmeter measures voltage, or the electrical potential difference between two
points. It is connected in parallel with the component being measured.
300+ QUESTIONS, VERIFIED ANSWERS &
DETAILED RATIONALES
Topics Covered
Section
1 Electrical Fundamentals - Ohm's Law, circuits, resistance, conductors,
AC/DC theory
2 Knots, Bends & Hitches - Figure Eight, Bowline, Half-Hitch, Square Knot,
Sheet Bend, Carrick Bend
3 Hand & Power Tools - Identification, proper use, and safety precautions
4 Workplace Safety - OSHA standards, NFPA 70E, lockout/tagout, PPE
5 Materials & Construction - Conduit types, wiring methods, grounding,
installation practices
6 Mechanical Aptitude - Tools, mechanical advantage, basic physics
7 Mathematics -Arithmetic, algebra, geometry, electrical calculations
8 Situational Judgment - Decision-making, prioritization, interpersonal
skills
,SECTION 1: ELECTRICAL FUNDAMENTALS
Q1. What is the unit of electric resistance?
A) Volt
B) Ampere
C) Ohm
D) Watt
Answer: C
Rationale: Resistance is measured in ohms (Ω), defined by Ohm's Law as V = I × R. Volts
measure electromotive force, amperes measure current, and watts measure power.
Q2. Which material is the best conductor of electricity?
A) Aluminum
B) Copper
C) Steel
D) PVC
Answer: B
Rationale: Copper has the highest conductivity among common wiring materials, surpassing
aluminum and far exceeding non-conductors like steel or PVC.
,Q3. In a series circuit, if one component fails open, the entire circuit:
A) Continues to operate at reduced voltage
B) Remains fully functional
C) Loses all voltage across each component
D) Stops current flow completely
Answer: D
Rationale: An open in a series path breaks the single continuous loop, halting current flow
throughout the circuit. This is a fundamental characteristic of series circuits.
Q4. The standard frequency of AC power supplied in the United States is:
A) 25 Hz
B) 50 Hz
C) 60 Hz
D) 100 Hz
Answer: C
Rationale: U.S. utility grids operate at 60 hertz (Hz), whereas many other countries use 50 Hz.
Q5. Which of the following is the correct formula for Ohm's Law?
A) V = I / R
B) V = I × R
C) V = R / I
D) V = P × I
, Answer: B
Rationale: Ohm's Law states that voltage (V) equals current (I) multiplied by resistance (R): V =
I × R.
Q6. Which unit is used to measure electric current?
A) Ohm
B) Volt
C) Watt
D) Ampere
Answer: D
Rationale: Electric current is measured in amperes (A). Voltage is measured in volts, resistance
in ohms, and power in watts.
Q7. What does a voltmeter measure?
A) Electrical potential difference
B) Resistance
C) Current flow
D) Electrical power
Answer: A
Rationale: A voltmeter measures voltage, or the electrical potential difference between two
points. It is connected in parallel with the component being measured.
