CSLB C10 EXAM 4 ACTUAL TEST 2026/2027 WITH
COMPLETE ACCURATE QUESTIONS AND CORRECT
DETAILED ANSWERS (CORRECT VERIFIED
SOLUTIONS) A NEW UPDATED VERSION
|GUARANTEED PASS A+
1. What is the best first step when planning an electrical installation?
A. Order all materials
B. Review plans, specifications, and site conditions
C. Energize the service
D. Install devices
Correct Answer: B
Rationale: Reviewing project documents and actual site conditions establishes the scope,
equipment requirements, circuit locations, and potential conflicts before installation begins.
2. A 120-V circuit supplies a 12-A load. What is the approximate power?
A. 120 W
B. 720 W
C. 1,440 W
D. 2,400 W
Correct Answer: C
Rationale:
P=V×I
P = 120 × 12 = 1,440 W.
3. A 240-V load consumes 3,600 W. Approximately how much current does it
draw?
A. 10 A
B. 12 A
C. 15 A
D. 20 A
,Correct Answer: C
Rationale:
I=P÷V
I = 3,600 ÷ 240 = 15 A.
4. What is the main purpose of evaluating an existing electrical system before
adding a large load?
A. Determine whether adequate capacity exists
B. Determine paint requirements
C. Reduce the building height
D. Eliminate inspections
Correct Answer: A
Rationale: The existing service, feeders, panels, conductors, and protective devices must be
evaluated to determine whether the proposed load can be safely accommodated.
5. Which document is most useful for identifying circuits associated with a
panel?
A. Panel schedule
B. Payroll sheet
C. Purchase receipt
D. Safety meeting log
Correct Answer: A
Rationale: Panel schedules identify circuits, breakers, loads, and related panel information.
6. What is Ohm's law?
A. V = IR
B. P = V + I
C. R = V + I
D. I = V × R
Correct Answer: A
, Rationale: Ohm's law establishes the relationship V = I × R.
7. A 30-Ω load connected to 120 V draws:
A. 2 A
B. 4 A
C. 6 A
D. 8 A
Correct Answer: B
Rationale:
I = V/R
I = 120/30 = 4 A.
8. What generally increases voltage drop?
A. Shorter conductor length
B. Lower current
C. Longer conductor length
D. Lower resistance
Correct Answer: C
Rationale: A longer conductor generally has greater resistance, resulting in greater voltage drop
when current flows.
9. What is the purpose of a material takeoff?
A. Determine material quantities
B. Measure voltage
C. Test insulation
D. Energize equipment
Correct Answer: A
Rationale: A material takeoff identifies and quantifies the materials required for a project.
COMPLETE ACCURATE QUESTIONS AND CORRECT
DETAILED ANSWERS (CORRECT VERIFIED
SOLUTIONS) A NEW UPDATED VERSION
|GUARANTEED PASS A+
1. What is the best first step when planning an electrical installation?
A. Order all materials
B. Review plans, specifications, and site conditions
C. Energize the service
D. Install devices
Correct Answer: B
Rationale: Reviewing project documents and actual site conditions establishes the scope,
equipment requirements, circuit locations, and potential conflicts before installation begins.
2. A 120-V circuit supplies a 12-A load. What is the approximate power?
A. 120 W
B. 720 W
C. 1,440 W
D. 2,400 W
Correct Answer: C
Rationale:
P=V×I
P = 120 × 12 = 1,440 W.
3. A 240-V load consumes 3,600 W. Approximately how much current does it
draw?
A. 10 A
B. 12 A
C. 15 A
D. 20 A
,Correct Answer: C
Rationale:
I=P÷V
I = 3,600 ÷ 240 = 15 A.
4. What is the main purpose of evaluating an existing electrical system before
adding a large load?
A. Determine whether adequate capacity exists
B. Determine paint requirements
C. Reduce the building height
D. Eliminate inspections
Correct Answer: A
Rationale: The existing service, feeders, panels, conductors, and protective devices must be
evaluated to determine whether the proposed load can be safely accommodated.
5. Which document is most useful for identifying circuits associated with a
panel?
A. Panel schedule
B. Payroll sheet
C. Purchase receipt
D. Safety meeting log
Correct Answer: A
Rationale: Panel schedules identify circuits, breakers, loads, and related panel information.
6. What is Ohm's law?
A. V = IR
B. P = V + I
C. R = V + I
D. I = V × R
Correct Answer: A
, Rationale: Ohm's law establishes the relationship V = I × R.
7. A 30-Ω load connected to 120 V draws:
A. 2 A
B. 4 A
C. 6 A
D. 8 A
Correct Answer: B
Rationale:
I = V/R
I = 120/30 = 4 A.
8. What generally increases voltage drop?
A. Shorter conductor length
B. Lower current
C. Longer conductor length
D. Lower resistance
Correct Answer: C
Rationale: A longer conductor generally has greater resistance, resulting in greater voltage drop
when current flows.
9. What is the purpose of a material takeoff?
A. Determine material quantities
B. Measure voltage
C. Test insulation
D. Energize equipment
Correct Answer: A
Rationale: A material takeoff identifies and quantifies the materials required for a project.
