LADWP ELECTRICAL MECHANIC NEWEST
EVALUATED EXAM PRACTICE QUESTIONS
2025 -2026| ORIGINAL QUESTIONS &
ANSWERS | DETAILED RATIONALES
|*HINTED* COMPLETE EXAM PREP
GRADED A+ **INSTANT DOWNLOAD PDF**
1. A 120 V DC control circuit contains a 24 Ω resistance. What current should
be expected under steady-state conditions?
A. 2 A
B. 4 A
Answer: C. 5 A
D. 6 A
Using Ohm’s law, I = V/R = 120/24 = 5 A.
2. A technician measures 48 V across a resistor while the circuit current is 2 A.
What is the resistance?
A. 12 Ω
Answer: B. 24 Ω
C. 48 Ω
D. 96 Ω
R = V/I = 48/2 = 24 Ω.
3. Two resistors of 10 Ω and 15 Ω are connected in series across a 50 V source.
What current flows through the circuit?
A. 1 A
B. 1.5 A
,Answer: C. 2 A
D. 2.5 A
The total resistance is 25 Ω. Therefore, I = 50/25 = 2 A.
4. A 20 Ω resistor and a 30 Ω resistor are connected in parallel across a 120 V
supply. What is the total circuit current?
A. 4 A
B. 6 A
Answer: C. 10 A
D. 12 A
The equivalent resistance is 12 Ω, so total current is 120/12 = 10 A.
5. A 240 V motor draws 15 A at a power factor of 0.80. What is its
approximate real input power?
A. 2.40 kW
Answer: B. 2.88 kW
C. 3.60 kW
D. 4.32 kW
For a single-phase load, P = VI × PF = 240 × 15 × 0.80 = 2,880 W.
6. A 480 V three-phase load draws 20 A at a power factor of 0.90.
Approximately how much real power does it consume?
A. 8.32 kW
B. 12.47 kW
Answer: C. 14.97 kW
D. 17.28 kW
Three-phase power is P = √3 × V × I × PF, giving approximately 14.97 kW.
7. A technician must measure current through a conductor without opening
the circuit. Which instrument is most appropriate?
A. Megohmmeter
B. Voltmeter
, Answer: C. Clamp ammeter
D. Ohmmeter
A clamp ammeter measures current by sensing the magnetic field around the
conductor.
8. Before measuring resistance with a conventional ohmmeter, what should be
done first?
A. Increase the circuit voltage
B. Short the meter leads across the energized circuit
Answer: C. De-energize and isolate the circuit
D. Set the meter to AC voltage
Resistance measurements require the circuit to be de-energized so the meter can
safely apply its own test current.
9. A 500 V megohmmeter is used to test insulation resistance. The measured
value is dramatically lower than expected. What condition is most likely
indicated?
A. Excessive conductor capacitance only
B. Proper insulation
Answer: C. Insulation deterioration or contamination
D. An oversized conductor
Low insulation resistance commonly indicates moisture, contamination, damage,
or deteriorated insulation.
10.A technician measures 480 V line-to-line on a three-phase system.
Approximately what voltage should be measured line-to-neutral on a
balanced wye system?
A. 120 V
B. 208 V
Answer: C. 277 V
D. 480 V
EVALUATED EXAM PRACTICE QUESTIONS
2025 -2026| ORIGINAL QUESTIONS &
ANSWERS | DETAILED RATIONALES
|*HINTED* COMPLETE EXAM PREP
GRADED A+ **INSTANT DOWNLOAD PDF**
1. A 120 V DC control circuit contains a 24 Ω resistance. What current should
be expected under steady-state conditions?
A. 2 A
B. 4 A
Answer: C. 5 A
D. 6 A
Using Ohm’s law, I = V/R = 120/24 = 5 A.
2. A technician measures 48 V across a resistor while the circuit current is 2 A.
What is the resistance?
A. 12 Ω
Answer: B. 24 Ω
C. 48 Ω
D. 96 Ω
R = V/I = 48/2 = 24 Ω.
3. Two resistors of 10 Ω and 15 Ω are connected in series across a 50 V source.
What current flows through the circuit?
A. 1 A
B. 1.5 A
,Answer: C. 2 A
D. 2.5 A
The total resistance is 25 Ω. Therefore, I = 50/25 = 2 A.
4. A 20 Ω resistor and a 30 Ω resistor are connected in parallel across a 120 V
supply. What is the total circuit current?
A. 4 A
B. 6 A
Answer: C. 10 A
D. 12 A
The equivalent resistance is 12 Ω, so total current is 120/12 = 10 A.
5. A 240 V motor draws 15 A at a power factor of 0.80. What is its
approximate real input power?
A. 2.40 kW
Answer: B. 2.88 kW
C. 3.60 kW
D. 4.32 kW
For a single-phase load, P = VI × PF = 240 × 15 × 0.80 = 2,880 W.
6. A 480 V three-phase load draws 20 A at a power factor of 0.90.
Approximately how much real power does it consume?
A. 8.32 kW
B. 12.47 kW
Answer: C. 14.97 kW
D. 17.28 kW
Three-phase power is P = √3 × V × I × PF, giving approximately 14.97 kW.
7. A technician must measure current through a conductor without opening
the circuit. Which instrument is most appropriate?
A. Megohmmeter
B. Voltmeter
, Answer: C. Clamp ammeter
D. Ohmmeter
A clamp ammeter measures current by sensing the magnetic field around the
conductor.
8. Before measuring resistance with a conventional ohmmeter, what should be
done first?
A. Increase the circuit voltage
B. Short the meter leads across the energized circuit
Answer: C. De-energize and isolate the circuit
D. Set the meter to AC voltage
Resistance measurements require the circuit to be de-energized so the meter can
safely apply its own test current.
9. A 500 V megohmmeter is used to test insulation resistance. The measured
value is dramatically lower than expected. What condition is most likely
indicated?
A. Excessive conductor capacitance only
B. Proper insulation
Answer: C. Insulation deterioration or contamination
D. An oversized conductor
Low insulation resistance commonly indicates moisture, contamination, damage,
or deteriorated insulation.
10.A technician measures 480 V line-to-line on a three-phase system.
Approximately what voltage should be measured line-to-neutral on a
balanced wye system?
A. 120 V
B. 208 V
Answer: C. 277 V
D. 480 V
