IOWA MASTER ELECTRICIAN EXAM – QUESTIONS
AND ANSWERS | VERIFIED AND WELL DETAILED
ANSWERS | PLUS RATIONALES | GUARANTEED
PASS | LATEST EXAM UPDATE
Section 1: Electrical Theory and Fundamentals
Question 1
Ohm's Law states that current in a circuit is:
A) Equal to voltage multiplied by resistance
B) Equal to voltage divided by resistance
C) Equal to resistance divided by voltage
D) Equal to power divided by voltage
Answer: B
Rationale: Ohm's Law is expressed as I = V ÷ R, where current equals voltage
divided by resistance. This is a fundamental relationship in electrical theory that
every master electrician must understand .
Question 2
A 240V load drawing 10A consumes how many watts of power?
A) 240 W
B) 2,400 W
C) 24 W
D) 24,000 W
Answer: B
,Rationale: Power is calculated using the formula P = V × I. Therefore, 240V × 10A =
2,400 watts. This principle applies to all resistive loads and is essential for load
calculations .
Question 3
The unit of electrical resistance is the:
A) Volt
B) Ampere
C) Ohm
D) Watt
Answer: C
Rationale: The ohm (Ω) is the standard unit of electrical resistance, measuring how
much a material resists the flow of electric current .
Question 4
In a parallel circuit, what remains constant across each branch?
A) Current
B) Voltage
C) Resistance
D) Power
Answer: B
Rationale: In a parallel circuit, voltage remains the same across each branch. This
is a key distinction from series circuits, where current is constant instead .
Question 5
In a DC circuit, if the voltage is 12V and resistance is 4Ω, what is the current?
,A) 3A
B) 16A
C) 0.33A
D) 48A
Answer: A
Rationale: Using Ohm's Law, I = V/R = 12V ÷ 4Ω = 3A. This is a straightforward
application of the fundamental electrical formula .
Question 6
Alternating current (AC) differs from direct current (DC) because:
A) AC flows in one direction only
B) DC alternates direction periodically
C) AC changes direction periodically
D) DC is used for all household circuits
Answer: C
Rationale: AC (Alternating Current) reverses direction periodically, while DC (Direct
Current) flows in one constant direction. This fundamental difference affects how
each is used in electrical systems .
Section 2: National Electrical Code (NEC)
Question 7
Which NEC Article covers grounding and bonding requirements?
A) Article 210
B) Article 250
C) Article 300
D) Article 404
Answer: B
, Rationale: NEC Article 250 addresses all grounding and bonding requirements for
electrical systems. This is one of the most critical articles for master electricians to
master .
Question 8
The NEC is typically revised on what cycle?
A) Every 2 years
B) Every 3 years
C) Every 5 years
D) Every 10 years
Answer: B
Rationale: The National Electrical Code is updated on a 3-year cycle. The current
version adopted in Iowa is the 2023 NEC, effective January 1, 2024 .
Question 9
What is the purpose of a Ground Fault Circuit Interrupter (GFCI)?
A) Protect against overvoltage conditions
B) Protect against short circuits
C) Protect against ground faults
D) Protect against lightning strikes
Answer: C
Rationale: GFCIs protect against ground faults by detecting current imbalance
between hot and neutral conductors. They are required in bathrooms, kitchens,
and other wet locations .
Question 10
AND ANSWERS | VERIFIED AND WELL DETAILED
ANSWERS | PLUS RATIONALES | GUARANTEED
PASS | LATEST EXAM UPDATE
Section 1: Electrical Theory and Fundamentals
Question 1
Ohm's Law states that current in a circuit is:
A) Equal to voltage multiplied by resistance
B) Equal to voltage divided by resistance
C) Equal to resistance divided by voltage
D) Equal to power divided by voltage
Answer: B
Rationale: Ohm's Law is expressed as I = V ÷ R, where current equals voltage
divided by resistance. This is a fundamental relationship in electrical theory that
every master electrician must understand .
Question 2
A 240V load drawing 10A consumes how many watts of power?
A) 240 W
B) 2,400 W
C) 24 W
D) 24,000 W
Answer: B
,Rationale: Power is calculated using the formula P = V × I. Therefore, 240V × 10A =
2,400 watts. This principle applies to all resistive loads and is essential for load
calculations .
Question 3
The unit of electrical resistance is the:
A) Volt
B) Ampere
C) Ohm
D) Watt
Answer: C
Rationale: The ohm (Ω) is the standard unit of electrical resistance, measuring how
much a material resists the flow of electric current .
Question 4
In a parallel circuit, what remains constant across each branch?
A) Current
B) Voltage
C) Resistance
D) Power
Answer: B
Rationale: In a parallel circuit, voltage remains the same across each branch. This
is a key distinction from series circuits, where current is constant instead .
Question 5
In a DC circuit, if the voltage is 12V and resistance is 4Ω, what is the current?
,A) 3A
B) 16A
C) 0.33A
D) 48A
Answer: A
Rationale: Using Ohm's Law, I = V/R = 12V ÷ 4Ω = 3A. This is a straightforward
application of the fundamental electrical formula .
Question 6
Alternating current (AC) differs from direct current (DC) because:
A) AC flows in one direction only
B) DC alternates direction periodically
C) AC changes direction periodically
D) DC is used for all household circuits
Answer: C
Rationale: AC (Alternating Current) reverses direction periodically, while DC (Direct
Current) flows in one constant direction. This fundamental difference affects how
each is used in electrical systems .
Section 2: National Electrical Code (NEC)
Question 7
Which NEC Article covers grounding and bonding requirements?
A) Article 210
B) Article 250
C) Article 300
D) Article 404
Answer: B
, Rationale: NEC Article 250 addresses all grounding and bonding requirements for
electrical systems. This is one of the most critical articles for master electricians to
master .
Question 8
The NEC is typically revised on what cycle?
A) Every 2 years
B) Every 3 years
C) Every 5 years
D) Every 10 years
Answer: B
Rationale: The National Electrical Code is updated on a 3-year cycle. The current
version adopted in Iowa is the 2023 NEC, effective January 1, 2024 .
Question 9
What is the purpose of a Ground Fault Circuit Interrupter (GFCI)?
A) Protect against overvoltage conditions
B) Protect against short circuits
C) Protect against ground faults
D) Protect against lightning strikes
Answer: C
Rationale: GFCIs protect against ground faults by detecting current imbalance
between hot and neutral conductors. They are required in bathrooms, kitchens,
and other wet locations .
Question 10
