IEC SECOND YEAR FINAL EXAM
COMPREHENSIVE PRACTICE (2026/2027 EDITION)
150 Multiple-Choice Questions - Complete Practice Exam
Independent-Study Disclaimer
This practice exam is an independent study aid and is not affiliated with, endorsed by, or sponsored by the
Independent Electrical Contractors (IEC), the National Electrical Code, NFPA, or any other organization. It is
provided for educational and self-assessment purposes only and is not a substitute for official IEC coursework,
apprenticeship requirements, or current code references. Code and curriculum content are subject to change;
always verify against the current NEC and your program.
, Section 1: Electrical Theory - AC/DC Fundamentals, Ohm's Law, Power,
Circuits (20 questions)
Q1: Ohm's Law states that voltage (V) equals:
A. Power divided by voltage
B. Resistance divided by current
C. Current times time
D. Current times resistance (V = I × R) [CORRECT]
Correct Answer: D
Rationale: Ohm's Law is V = I × R, where voltage equals current times resistance. The other options do not
state Ohm's Law.
Q2: The power equation for an electrical circuit is:
A. P = V / I
B. P = R / I
C. P = V × I [CORRECT]
D. P = I / V
Correct Answer: C
Rationale: Power equals voltage times current (P = V × I). The other equations are not the power formula.
Q3: In the United States, a 60 Hz AC voltage reaches its negative peak how many times per second?
A. 60 times
B. 120 times [CORRECT]
C. 240 times
D. 360 times
Correct Answer: B
Rationale: A 60 Hz AC wave completes 60 cycles per second, and each cycle has one negative peak, so
there are 120 negative peaks per second. The other counts are incorrect.
Q4: In a series circuit, the total resistance is:
A. Less than the smallest resistance
B. The sum of all individual resistances [CORRECT]
C. Equal to the largest resistance only
D. The reciprocal of the sum
Correct Answer: B
Rationale: In a series circuit, total resistance equals the sum of all resistances. Parallel circuits use
reciprocal methods.
Q5: In a parallel circuit, the total current is:
A. The sum of the currents in each branch [CORRECT]
B. Equal to the current in one branch
C. Always zero
D. Equal to the voltage divided by total resistance only when branches are equal
Correct Answer: A
Rationale: In a parallel circuit, total current is the sum of the branch currents. The other options are incorrect.
IEC Second Year Final Exam - 2026/2027 Edition Page 2
, Q6: Which of the following units measures inductance?
A. Farad
B. Henry [CORRECT]
C. Ohm
D. Watt
Correct Answer: B
Rationale: Inductance is measured in henrys. Capacitance is measured in farads, resistance in ohms, and
power in watts.
Q7: Which of the following units measures capacitance?
A. Farad [CORRECT]
B. Henry
C. Ampere
D. Volt
Correct Answer: A
Rationale: Capacitance is measured in farads. The other units measure inductance, current, and voltage.
Q8: In an AC circuit containing only resistance, the current and voltage are:
A. 90 degrees out of phase
B. 180 degrees out of phase
C. In phase with each other [CORRECT]
D. Completely random
Correct Answer: C
Rationale: In a purely resistive AC circuit, current and voltage are in phase. Inductance and capacitance
create phase shifts.
Q9: In a purely inductive AC circuit, the current:
A. Lags the voltage by 90 degrees [CORRECT]
B. Leads the voltage by 90 degrees
C. Is in phase with the voltage
D. Is always zero
Correct Answer: A
Rationale: In a purely inductive circuit, current lags the voltage by 90 degrees. The other options describe
resistive or capacitive behavior.
Q10: In a purely capacitive AC circuit, the current:
A. Lags the voltage by 90 degrees
B. Is in phase with the voltage
C. Is constant
D. Leads the voltage by 90 degrees [CORRECT]
Correct Answer: D
Rationale: In a purely capacitive circuit, current leads the voltage by 90 degrees. The other options are
incorrect.
IEC Second Year Final Exam - 2026/2027 Edition Page 3
, Q11: Impedance (Z) in an AC circuit is the:
A. Same as resistance in all cases
B. Total opposition to current including resistance and reactance [CORRECT]
C. Opposition only from capacitors
D. Reciprocal of power
Correct Answer: B
Rationale: Impedance is the total opposition to AC current, combining resistance and reactance. It is not
simply resistance or a single reactance.
Q12: Power factor is defined as the ratio of:
A. Apparent power to reactive power
B. Voltage to current
C. True power to apparent power [CORRECT]
D. Resistance to reactance
Correct Answer: C
Rationale: Power factor is the ratio of true (real) power to apparent power. The other options do not define
power factor.
Q13: Reactive power in an AC circuit is measured in:
A. Volt-amperes reactive (VAR) [CORRECT]
B. Watts
C. Volt-amperes (VA)
D. Joules
Correct Answer: A
Rationale: Reactive power is measured in VAR. True power is measured in watts, and apparent power in
VA.
Q14: Apparent power in an AC circuit is expressed in:
A. Watts
B. VAR
C. Volt-amperes (VA) [CORRECT]
D. Ohms
Correct Answer: C
Rationale: Apparent power is expressed in volt-amperes (VA). True power is watts and reactive power is
VAR.
Q15: If a DC circuit has a voltage of 120 V and a resistance of 20 ohms, the current is:
A. 2.4 A
B. 2400 A
C. 6 A [CORRECT]
D. 0.16 A
Correct Answer: C
Rationale: Using Ohm's Law, I = V / R = = 6 A. The other values do not result from this calculation.
IEC Second Year Final Exam - 2026/2027 Edition Page 4
COMPREHENSIVE PRACTICE (2026/2027 EDITION)
150 Multiple-Choice Questions - Complete Practice Exam
Independent-Study Disclaimer
This practice exam is an independent study aid and is not affiliated with, endorsed by, or sponsored by the
Independent Electrical Contractors (IEC), the National Electrical Code, NFPA, or any other organization. It is
provided for educational and self-assessment purposes only and is not a substitute for official IEC coursework,
apprenticeship requirements, or current code references. Code and curriculum content are subject to change;
always verify against the current NEC and your program.
, Section 1: Electrical Theory - AC/DC Fundamentals, Ohm's Law, Power,
Circuits (20 questions)
Q1: Ohm's Law states that voltage (V) equals:
A. Power divided by voltage
B. Resistance divided by current
C. Current times time
D. Current times resistance (V = I × R) [CORRECT]
Correct Answer: D
Rationale: Ohm's Law is V = I × R, where voltage equals current times resistance. The other options do not
state Ohm's Law.
Q2: The power equation for an electrical circuit is:
A. P = V / I
B. P = R / I
C. P = V × I [CORRECT]
D. P = I / V
Correct Answer: C
Rationale: Power equals voltage times current (P = V × I). The other equations are not the power formula.
Q3: In the United States, a 60 Hz AC voltage reaches its negative peak how many times per second?
A. 60 times
B. 120 times [CORRECT]
C. 240 times
D. 360 times
Correct Answer: B
Rationale: A 60 Hz AC wave completes 60 cycles per second, and each cycle has one negative peak, so
there are 120 negative peaks per second. The other counts are incorrect.
Q4: In a series circuit, the total resistance is:
A. Less than the smallest resistance
B. The sum of all individual resistances [CORRECT]
C. Equal to the largest resistance only
D. The reciprocal of the sum
Correct Answer: B
Rationale: In a series circuit, total resistance equals the sum of all resistances. Parallel circuits use
reciprocal methods.
Q5: In a parallel circuit, the total current is:
A. The sum of the currents in each branch [CORRECT]
B. Equal to the current in one branch
C. Always zero
D. Equal to the voltage divided by total resistance only when branches are equal
Correct Answer: A
Rationale: In a parallel circuit, total current is the sum of the branch currents. The other options are incorrect.
IEC Second Year Final Exam - 2026/2027 Edition Page 2
, Q6: Which of the following units measures inductance?
A. Farad
B. Henry [CORRECT]
C. Ohm
D. Watt
Correct Answer: B
Rationale: Inductance is measured in henrys. Capacitance is measured in farads, resistance in ohms, and
power in watts.
Q7: Which of the following units measures capacitance?
A. Farad [CORRECT]
B. Henry
C. Ampere
D. Volt
Correct Answer: A
Rationale: Capacitance is measured in farads. The other units measure inductance, current, and voltage.
Q8: In an AC circuit containing only resistance, the current and voltage are:
A. 90 degrees out of phase
B. 180 degrees out of phase
C. In phase with each other [CORRECT]
D. Completely random
Correct Answer: C
Rationale: In a purely resistive AC circuit, current and voltage are in phase. Inductance and capacitance
create phase shifts.
Q9: In a purely inductive AC circuit, the current:
A. Lags the voltage by 90 degrees [CORRECT]
B. Leads the voltage by 90 degrees
C. Is in phase with the voltage
D. Is always zero
Correct Answer: A
Rationale: In a purely inductive circuit, current lags the voltage by 90 degrees. The other options describe
resistive or capacitive behavior.
Q10: In a purely capacitive AC circuit, the current:
A. Lags the voltage by 90 degrees
B. Is in phase with the voltage
C. Is constant
D. Leads the voltage by 90 degrees [CORRECT]
Correct Answer: D
Rationale: In a purely capacitive circuit, current leads the voltage by 90 degrees. The other options are
incorrect.
IEC Second Year Final Exam - 2026/2027 Edition Page 3
, Q11: Impedance (Z) in an AC circuit is the:
A. Same as resistance in all cases
B. Total opposition to current including resistance and reactance [CORRECT]
C. Opposition only from capacitors
D. Reciprocal of power
Correct Answer: B
Rationale: Impedance is the total opposition to AC current, combining resistance and reactance. It is not
simply resistance or a single reactance.
Q12: Power factor is defined as the ratio of:
A. Apparent power to reactive power
B. Voltage to current
C. True power to apparent power [CORRECT]
D. Resistance to reactance
Correct Answer: C
Rationale: Power factor is the ratio of true (real) power to apparent power. The other options do not define
power factor.
Q13: Reactive power in an AC circuit is measured in:
A. Volt-amperes reactive (VAR) [CORRECT]
B. Watts
C. Volt-amperes (VA)
D. Joules
Correct Answer: A
Rationale: Reactive power is measured in VAR. True power is measured in watts, and apparent power in
VA.
Q14: Apparent power in an AC circuit is expressed in:
A. Watts
B. VAR
C. Volt-amperes (VA) [CORRECT]
D. Ohms
Correct Answer: C
Rationale: Apparent power is expressed in volt-amperes (VA). True power is watts and reactive power is
VAR.
Q15: If a DC circuit has a voltage of 120 V and a resistance of 20 ohms, the current is:
A. 2.4 A
B. 2400 A
C. 6 A [CORRECT]
D. 0.16 A
Correct Answer: C
Rationale: Using Ohm's Law, I = V / R = = 6 A. The other values do not result from this calculation.
IEC Second Year Final Exam - 2026/2027 Edition Page 4
