AR EL Electrical Contractor
Exam Questions and Correct
Answers (Verified Answers)
Plus Rationale 2027 Q&A|
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Question 1
What is the primary purpose of an overcurrent protective device, such
as a circuit breaker or fuse?
A. To increase the voltage supplied to a circuit
B. To prevent all electrical shocks
C. To protect conductors and equipment against excessive current
D. To improve the power factor of a circuit
,Rationale: Overcurrent protective devices interrupt current when it
exceeds a predetermined level due to an overload or short circuit. This
helps prevent excessive conductor heating, insulation damage, and
fire. They do not provide complete protection against electric shock,
which requires appropriate grounding, bonding, and other protective
measures.
Question 2
A 120-volt circuit supplies a load drawing 10 amperes. What is the
approximate power consumed by the load?
A. 12 watts
B. 120 watts
C. 1,200 watts
D. 12,000 watts
Rationale: Electrical power in a single-phase circuit can be calculated
using P = V × I. Multiplying 120 volts by 10 amperes gives 1,200 watts.
This relationship is useful when calculating loads, estimating energy
consumption, and selecting electrical equipment.
Question 3
,What is the primary function of an equipment grounding conductor
(EGC)?
A. To carry normal neutral current
B. To increase circuit voltage
C. To serve as the primary current-carrying conductor
D. To provide a low-impedance path for fault current
Rationale: An equipment grounding conductor provides a conductive
path for fault current back toward the electrical source. This helps
operate the overcurrent protective device quickly when a fault
energizes exposed conductive equipment parts. Under normal
operating conditions, the EGC should not carry current.
Question 4
Which instrument is most appropriate for measuring the current
flowing through an individual conductor without disconnecting it?
A. Megohmmeter
B. Clamp ammeter
C. Non-contact voltage detector
D. Insulation resistance tester
, Rationale: A clamp ammeter measures current by sensing the
magnetic field around a conductor. The conductor can remain
connected and energized when the measurement is performed using
an appropriately rated instrument and safe procedures. A
conventional ammeter generally must be connected in series with the
circuit.
Question 5
What is the main purpose of electrical bonding?
A. To increase resistance between metal components
B. To eliminate the need for overcurrent protection
C. To establish electrical continuity between conductive parts
D. To prevent all voltage fluctuations
Rationale: Bonding connects conductive components together to
establish electrical continuity. In electrical systems, bonding helps
provide an effective fault-current path and reduces dangerous
potential differences between conductive parts. Bonding is distinct
from grounding, although the two functions work together in an
electrical installation.
Question 6
Exam Questions and Correct
Answers (Verified Answers)
Plus Rationale 2027 Q&A|
Instant Download Pdf
Question 1
What is the primary purpose of an overcurrent protective device, such
as a circuit breaker or fuse?
A. To increase the voltage supplied to a circuit
B. To prevent all electrical shocks
C. To protect conductors and equipment against excessive current
D. To improve the power factor of a circuit
,Rationale: Overcurrent protective devices interrupt current when it
exceeds a predetermined level due to an overload or short circuit. This
helps prevent excessive conductor heating, insulation damage, and
fire. They do not provide complete protection against electric shock,
which requires appropriate grounding, bonding, and other protective
measures.
Question 2
A 120-volt circuit supplies a load drawing 10 amperes. What is the
approximate power consumed by the load?
A. 12 watts
B. 120 watts
C. 1,200 watts
D. 12,000 watts
Rationale: Electrical power in a single-phase circuit can be calculated
using P = V × I. Multiplying 120 volts by 10 amperes gives 1,200 watts.
This relationship is useful when calculating loads, estimating energy
consumption, and selecting electrical equipment.
Question 3
,What is the primary function of an equipment grounding conductor
(EGC)?
A. To carry normal neutral current
B. To increase circuit voltage
C. To serve as the primary current-carrying conductor
D. To provide a low-impedance path for fault current
Rationale: An equipment grounding conductor provides a conductive
path for fault current back toward the electrical source. This helps
operate the overcurrent protective device quickly when a fault
energizes exposed conductive equipment parts. Under normal
operating conditions, the EGC should not carry current.
Question 4
Which instrument is most appropriate for measuring the current
flowing through an individual conductor without disconnecting it?
A. Megohmmeter
B. Clamp ammeter
C. Non-contact voltage detector
D. Insulation resistance tester
, Rationale: A clamp ammeter measures current by sensing the
magnetic field around a conductor. The conductor can remain
connected and energized when the measurement is performed using
an appropriately rated instrument and safe procedures. A
conventional ammeter generally must be connected in series with the
circuit.
Question 5
What is the main purpose of electrical bonding?
A. To increase resistance between metal components
B. To eliminate the need for overcurrent protection
C. To establish electrical continuity between conductive parts
D. To prevent all voltage fluctuations
Rationale: Bonding connects conductive components together to
establish electrical continuity. In electrical systems, bonding helps
provide an effective fault-current path and reduces dangerous
potential differences between conductive parts. Bonding is distinct
from grounding, although the two functions work together in an
electrical installation.
Question 6
