Electrical Mechanic-Test Technician Study Guide Test with questions and
answers with rationales
Section 1: Basic Electrical Theory (Questions 1-25)
Question 1
What is the SI unit of electrical charge, equal to the quantity of electricity
conveyed in one second by a current of one ampere?
A) Ohm
B) Volt
C) Coulomb
D) Watt
Answer: C
Rationale: The coulomb (C) is the standard unit of electric charge. One coulomb is
defined as the amount of charge transported by a steady current of one ampere
flowing for one second. This is a fundamental definition in electrical engineering,
differentiating charge (coulombs) from current (amperes) .
Question 2
Which of the following has the LEAST amount of resistance to electric current?
,A) Iron
B) Rubber
C) Copper
D) Wood
Answer: C
Rationale: Copper is one of the best conductors of electricity due to its atomic
structure, which allows free electrons to move easily. Rubber and wood are
insulators, and iron has higher resistivity than copper .
Question 3
The opposition to the flow of electrons is measured in:
A) Amperes
B) Volts
C) Ohms (Ω)
D) Watts
Answer: C
,Rationale: Resistance, measured in Ohms (Ω), quantifies how much a material
opposes the flow of electric current. Amperes measure current flow, volts
measure electrical pressure, and watts measure power .
Question 4
In a DC circuit, watts divided by volts equals:
A) Resistance
B) Power
C) Current
D) Conductance
Answer: C
Rationale: According to the power formula
P
=
V
×
I
P=V×I, rearranging gives
I
, =
P
/
V
I=P/V. Therefore, watts divided by volts equals current in amperes .
Question 5
Which of the following is NOT a basic component of an atom?
A) Proton
B) Neutron
C) Electron
D) Ion
Answer: D
Rationale: Protons, neutrons, and electrons are the three fundamental subatomic
particles that make up an atom. An ion is an atom or molecule that has gained or
lost electrons, giving it a net charge—it is not a basic component .
Question 6
The difference in electrical potential between two points is called:
answers with rationales
Section 1: Basic Electrical Theory (Questions 1-25)
Question 1
What is the SI unit of electrical charge, equal to the quantity of electricity
conveyed in one second by a current of one ampere?
A) Ohm
B) Volt
C) Coulomb
D) Watt
Answer: C
Rationale: The coulomb (C) is the standard unit of electric charge. One coulomb is
defined as the amount of charge transported by a steady current of one ampere
flowing for one second. This is a fundamental definition in electrical engineering,
differentiating charge (coulombs) from current (amperes) .
Question 2
Which of the following has the LEAST amount of resistance to electric current?
,A) Iron
B) Rubber
C) Copper
D) Wood
Answer: C
Rationale: Copper is one of the best conductors of electricity due to its atomic
structure, which allows free electrons to move easily. Rubber and wood are
insulators, and iron has higher resistivity than copper .
Question 3
The opposition to the flow of electrons is measured in:
A) Amperes
B) Volts
C) Ohms (Ω)
D) Watts
Answer: C
,Rationale: Resistance, measured in Ohms (Ω), quantifies how much a material
opposes the flow of electric current. Amperes measure current flow, volts
measure electrical pressure, and watts measure power .
Question 4
In a DC circuit, watts divided by volts equals:
A) Resistance
B) Power
C) Current
D) Conductance
Answer: C
Rationale: According to the power formula
P
=
V
×
I
P=V×I, rearranging gives
I
, =
P
/
V
I=P/V. Therefore, watts divided by volts equals current in amperes .
Question 5
Which of the following is NOT a basic component of an atom?
A) Proton
B) Neutron
C) Electron
D) Ion
Answer: D
Rationale: Protons, neutrons, and electrons are the three fundamental subatomic
particles that make up an atom. An ion is an atom or molecule that has gained or
lost electrons, giving it a net charge—it is not a basic component .
Question 6
The difference in electrical potential between two points is called:
