LADWP ELECTRICAL CRAFT HELPER
CIRCUITS & COMPONENTS EXAM WITH
ACTUAL QUESTIONS AND VERIFIED
ANSWERS, PLUS EXPLAINED
RATIONALES/EXPERT VERIFIED FOR
GUARANTEED 100% PASS 2026/LATEST
UPDATE/INSTANT DOWNLOAD PDF
1.
A 120-V branch circuit supplies a purely resistive heating element with a
resistance of 24 Ω. Assuming the source voltage remains at 120 V, what
current should flow through the element?
A. 0.2 A
B. 2 A
C. 5 A
D. 24 A
Answer: C. 5 A
Rationale: Ohm’s law states that current equals voltage divided by
resistance: I = V/R. Therefore, I = 120 V ÷ 24 Ω = 5 A. The resistance
limits the current to 5 amperes under the stated conditions.
2.
Two resistors rated at 10 Ω and 20 Ω are connected in series across a 60-
V source. Which statement correctly describes the circuit?
A. The total resistance is 6.67 Ω and the current is 9 A
B. The total resistance is 30 Ω and the circuit current is 2 A
C. The total resistance is 30 Ω and the current through the 20-Ω resistor
1
,is 3 A
D. The total resistance is 200 Ω and the circuit current is 0.3 A
Answer: B. The total resistance is 30 Ω and the circuit current is 2 A
Rationale: Series resistances add directly: Rtotal = 10 Ω + 20 Ω = 30
Ω. Applying Ohm’s law gives I = 60 V ÷ 30 Ω = 2 A. Because series
components carry the same current, 2 A flows through both resistors.
3.
A technician connects two 12-Ω resistors in parallel across a 24-V
source. What is the total current supplied by the source?
A. 1 A
B. 2 A
C. 4 A
D. 8 A
Answer: D. 4 A
Rationale: Two equal 12-Ω resistors in parallel have an equivalent
resistance of 6 Ω. The source current is therefore I = 24 V ÷ 6 Ω = 4 A.
Each resistor individually carries 2 A, and the branch currents add to
4 A.
4.
Which electrical quantity is measured in ohms and represents opposition
to the flow of electric current?
A. Voltage
B. Resistance
C. Power
D. Capacitance
2
,Answer: B. Resistance
Rationale: Resistance is measured in ohms (Ω) and describes
opposition to current flow. Voltage is measured in volts, power in
watts, and capacitance in farads.
5.
A voltmeter is being used to measure the voltage across an energized
resistor. How should the meter be connected?
A. In series with the resistor
B. In parallel with the resistor
C. Between the resistor and equipment ground only
D. In series with the circuit fuse
Answer: B. In parallel with the resistor
Rationale: A voltmeter measures potential difference between two
points, so its probes are placed across the component or circuit section
being measured. Voltmeters have high internal resistance, minimizing
the current they draw from the circuit.
6.
An electrician needs to determine whether a disconnected wire has
continuity from one end to the other. Which meter function is most
appropriate?
A. AC voltage
B. DC voltage
C. Resistance/continuity
D. Frequency only
Answer: C. Resistance/continuity
3
, Rationale: A continuity test determines whether there is a low-
resistance conductive path between two points. The circuit should be
de-energized before using an ohmmeter or continuity function because
applying external voltage to the meter can damage the instrument and
create a hazardous condition.
7.
A 60-W incandescent lamp is connected to a 120-V source.
Approximately how much current does it draw under normal operating
conditions?
A. 0.05 A
B. 0.5 A
C. 2 A
D. 7.2 A
Answer: B. 0.5 A
Rationale: Using P = VI, current is I = P/V = 60 W ÷ 120 V = 0.5 A.
This assumes the lamp is operating at its rated voltage and its stated
power represents its operating power.
8.
Which component is specifically designed to interrupt a circuit when
excessive current causes its fusible element to melt?
A. Relay
B. Capacitor
C. Fuse
D. Transformer
Answer: C. Fuse
4
CIRCUITS & COMPONENTS EXAM WITH
ACTUAL QUESTIONS AND VERIFIED
ANSWERS, PLUS EXPLAINED
RATIONALES/EXPERT VERIFIED FOR
GUARANTEED 100% PASS 2026/LATEST
UPDATE/INSTANT DOWNLOAD PDF
1.
A 120-V branch circuit supplies a purely resistive heating element with a
resistance of 24 Ω. Assuming the source voltage remains at 120 V, what
current should flow through the element?
A. 0.2 A
B. 2 A
C. 5 A
D. 24 A
Answer: C. 5 A
Rationale: Ohm’s law states that current equals voltage divided by
resistance: I = V/R. Therefore, I = 120 V ÷ 24 Ω = 5 A. The resistance
limits the current to 5 amperes under the stated conditions.
2.
Two resistors rated at 10 Ω and 20 Ω are connected in series across a 60-
V source. Which statement correctly describes the circuit?
A. The total resistance is 6.67 Ω and the current is 9 A
B. The total resistance is 30 Ω and the circuit current is 2 A
C. The total resistance is 30 Ω and the current through the 20-Ω resistor
1
,is 3 A
D. The total resistance is 200 Ω and the circuit current is 0.3 A
Answer: B. The total resistance is 30 Ω and the circuit current is 2 A
Rationale: Series resistances add directly: Rtotal = 10 Ω + 20 Ω = 30
Ω. Applying Ohm’s law gives I = 60 V ÷ 30 Ω = 2 A. Because series
components carry the same current, 2 A flows through both resistors.
3.
A technician connects two 12-Ω resistors in parallel across a 24-V
source. What is the total current supplied by the source?
A. 1 A
B. 2 A
C. 4 A
D. 8 A
Answer: D. 4 A
Rationale: Two equal 12-Ω resistors in parallel have an equivalent
resistance of 6 Ω. The source current is therefore I = 24 V ÷ 6 Ω = 4 A.
Each resistor individually carries 2 A, and the branch currents add to
4 A.
4.
Which electrical quantity is measured in ohms and represents opposition
to the flow of electric current?
A. Voltage
B. Resistance
C. Power
D. Capacitance
2
,Answer: B. Resistance
Rationale: Resistance is measured in ohms (Ω) and describes
opposition to current flow. Voltage is measured in volts, power in
watts, and capacitance in farads.
5.
A voltmeter is being used to measure the voltage across an energized
resistor. How should the meter be connected?
A. In series with the resistor
B. In parallel with the resistor
C. Between the resistor and equipment ground only
D. In series with the circuit fuse
Answer: B. In parallel with the resistor
Rationale: A voltmeter measures potential difference between two
points, so its probes are placed across the component or circuit section
being measured. Voltmeters have high internal resistance, minimizing
the current they draw from the circuit.
6.
An electrician needs to determine whether a disconnected wire has
continuity from one end to the other. Which meter function is most
appropriate?
A. AC voltage
B. DC voltage
C. Resistance/continuity
D. Frequency only
Answer: C. Resistance/continuity
3
, Rationale: A continuity test determines whether there is a low-
resistance conductive path between two points. The circuit should be
de-energized before using an ohmmeter or continuity function because
applying external voltage to the meter can damage the instrument and
create a hazardous condition.
7.
A 60-W incandescent lamp is connected to a 120-V source.
Approximately how much current does it draw under normal operating
conditions?
A. 0.05 A
B. 0.5 A
C. 2 A
D. 7.2 A
Answer: B. 0.5 A
Rationale: Using P = VI, current is I = P/V = 60 W ÷ 120 V = 0.5 A.
This assumes the lamp is operating at its rated voltage and its stated
power represents its operating power.
8.
Which component is specifically designed to interrupt a circuit when
excessive current causes its fusible element to melt?
A. Relay
B. Capacitor
C. Fuse
D. Transformer
Answer: C. Fuse
4
