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CSLB C10 TEST 1 | 120 QUESTIONS AND ANSWERS (2026
/ 2027) (VERIFIED ANSWERS) COMPLETE FREQUENTLY
MOST TESTED QUESTIONS WITH COMPLETE SOLUTION
/GET IT 100% ACCURATE!(GRADED A+)
1. Under Ohm’s Law, if a circuit has a voltage of 240 volts and a
resistance of 30 ohms, what current will flow through the circuit?
A. 2 amperes
B. 8 amperes
C. 12 amperes
D. 30 amperes
Answer: B. 8 amperes
Solution: Ohm’s Law is I = E ÷ R. Therefore, 240 volts ÷ 30 ohms = 8
amperes. Knowing how to rearrange the basic Ohm’s Law formulas is
essential for electrical calculations.
2. A 1,500-watt electric heater operates on a 120-volt circuit.
Approximately how much current does the heater draw when operating
at its rated voltage?
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A. 8.0 amperes
B. 10.0 amperes
C. 12.5 amperes
D. 15.0 amperes
Answer: C. 12.5 amperes
Solution: Use P = E × I, so I = P ÷ E. Thus, 1,500 watts ÷ 120 volts = 12.5
amperes.
3. In a parallel circuit containing three equal resistors, what happens to
the total resistance compared with the resistance of one individual
resistor?
A. The total resistance is greater than one resistor.
B. The total resistance equals the sum of all three resistors.
C. The total resistance is less than the resistance of any individual
resistor.
D. The total resistance becomes infinite.
Answer: C. The total resistance is less than the resistance of any
individual resistor.
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Solution: Adding additional resistance paths in parallel decreases total
circuit resistance. For three identical resistors, the equivalent resistance
is one-third of the resistance of a single resistor.
4. Which statement correctly describes the relationship between
voltage, current, and resistance?
A. Voltage equals current multiplied by resistance.
B. Voltage equals resistance divided by current.
C. Current equals voltage multiplied by resistance.
D. Resistance equals voltage multiplied by current.
Answer: A. Voltage equals current multiplied by resistance.
Solution: The fundamental Ohm’s Law relationship is E = I × R. The other
forms are I = E ÷ R and R = E ÷ I.
5. Which factor combination has the greatest effect on voltage drop in a
branch circuit conductor?
A. Conductor color, insulation color, and box size
B. Conductor length, conductor resistance, and current flow
C. Raceway color, panel size, and grounding-electrode type
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D. Switch type, fixture color, and junction-box shape
Answer: B. Conductor length, conductor resistance, and current flow
Solution: Voltage drop is directly related to current and conductor
resistance. Conductor resistance is affected by factors including
conductor size and length. Longer conductors generally have greater
resistance, increasing voltage drop for a given current.
6. Which type of electrical circuit provides multiple paths for current to
flow?
A. Series circuit
B. Open circuit
C. Parallel circuit
D. Shorted circuit
Answer: C. Parallel circuit
Solution: A parallel circuit contains two or more current paths. This is
why loads connected in parallel can continue operating independently if
another branch is opened.
CSLB C10 TEST 1 | 120 QUESTIONS AND ANSWERS (2026
/ 2027) (VERIFIED ANSWERS) COMPLETE FREQUENTLY
MOST TESTED QUESTIONS WITH COMPLETE SOLUTION
/GET IT 100% ACCURATE!(GRADED A+)
1. Under Ohm’s Law, if a circuit has a voltage of 240 volts and a
resistance of 30 ohms, what current will flow through the circuit?
A. 2 amperes
B. 8 amperes
C. 12 amperes
D. 30 amperes
Answer: B. 8 amperes
Solution: Ohm’s Law is I = E ÷ R. Therefore, 240 volts ÷ 30 ohms = 8
amperes. Knowing how to rearrange the basic Ohm’s Law formulas is
essential for electrical calculations.
2. A 1,500-watt electric heater operates on a 120-volt circuit.
Approximately how much current does the heater draw when operating
at its rated voltage?
,2|Page
A. 8.0 amperes
B. 10.0 amperes
C. 12.5 amperes
D. 15.0 amperes
Answer: C. 12.5 amperes
Solution: Use P = E × I, so I = P ÷ E. Thus, 1,500 watts ÷ 120 volts = 12.5
amperes.
3. In a parallel circuit containing three equal resistors, what happens to
the total resistance compared with the resistance of one individual
resistor?
A. The total resistance is greater than one resistor.
B. The total resistance equals the sum of all three resistors.
C. The total resistance is less than the resistance of any individual
resistor.
D. The total resistance becomes infinite.
Answer: C. The total resistance is less than the resistance of any
individual resistor.
,3|Page
Solution: Adding additional resistance paths in parallel decreases total
circuit resistance. For three identical resistors, the equivalent resistance
is one-third of the resistance of a single resistor.
4. Which statement correctly describes the relationship between
voltage, current, and resistance?
A. Voltage equals current multiplied by resistance.
B. Voltage equals resistance divided by current.
C. Current equals voltage multiplied by resistance.
D. Resistance equals voltage multiplied by current.
Answer: A. Voltage equals current multiplied by resistance.
Solution: The fundamental Ohm’s Law relationship is E = I × R. The other
forms are I = E ÷ R and R = E ÷ I.
5. Which factor combination has the greatest effect on voltage drop in a
branch circuit conductor?
A. Conductor color, insulation color, and box size
B. Conductor length, conductor resistance, and current flow
C. Raceway color, panel size, and grounding-electrode type
, 4|Page
D. Switch type, fixture color, and junction-box shape
Answer: B. Conductor length, conductor resistance, and current flow
Solution: Voltage drop is directly related to current and conductor
resistance. Conductor resistance is affected by factors including
conductor size and length. Longer conductors generally have greater
resistance, increasing voltage drop for a given current.
6. Which type of electrical circuit provides multiple paths for current to
flow?
A. Series circuit
B. Open circuit
C. Parallel circuit
D. Shorted circuit
Answer: C. Parallel circuit
Solution: A parallel circuit contains two or more current paths. This is
why loads connected in parallel can continue operating independently if
another branch is opened.
