1. In a balanced three-phase system, the current in the neutral wire is:
A. Maximum
B. Zero
C. Equal to phase current
D. Double the phase current
Answer: B) Zero
Rationale: A balanced system cancels neutral current.
2. What is the main purpose of a GFCI outlet?
A. Increase circuit capacity
B. Prevent overload
C. Protect against ground faults
D. Reduce energy consumption
Answer: C) Protect against ground faults
Rationale: GFCI outlets detect and interrupt ground faults to prevent
electrical shocks.
3. A circuit with zero resistance is called a:
A. Closed circuit
B. Open circuit
,C. Short circuit
D. Parallel circuit
Answer: C) Short circuit
Rationale: A short circuit occurs when resistance is negligible, leading
to excessive current flow.
4. What is the primary role of an insulator in an electrical system?
A. Conduct electricity
B. Provide support
C. Prevent current flow
D. Reduce voltage
Answer: C) Prevent current flow
Rationale: Insulators block the flow of electricity to enhance safety.
5. What is the role of a capacitor in a circuit?
A. Store electrical energy
B. Reduce resistance
C. Convert AC to DC
D. Measure voltage
Answer: A) Store electrical energy
Rationale: Capacitors temporarily store and release electrical energy.
, 6. The primary purpose of a ground wire is to:
A. Carry current to the load
B. Prevent electrical shock
C. Increase voltage
D. Maintain resistance
Answer: B) Prevent electrical shock
Rationale: Ground wires direct stray currents safely into the earth,
reducing shock risk.
7. The formula P=I2RP = I^2RP=I2R is used to calculate:
A. Voltage
B. Current
C. Power
D. Resistance
Answer: C) Power
Rationale: This formula calculates power based on current and
resistance.
8. Which formula represents electrical resistance?
A. R = V/I
B. R = VI
C. R = P/V
A. Maximum
B. Zero
C. Equal to phase current
D. Double the phase current
Answer: B) Zero
Rationale: A balanced system cancels neutral current.
2. What is the main purpose of a GFCI outlet?
A. Increase circuit capacity
B. Prevent overload
C. Protect against ground faults
D. Reduce energy consumption
Answer: C) Protect against ground faults
Rationale: GFCI outlets detect and interrupt ground faults to prevent
electrical shocks.
3. A circuit with zero resistance is called a:
A. Closed circuit
B. Open circuit
,C. Short circuit
D. Parallel circuit
Answer: C) Short circuit
Rationale: A short circuit occurs when resistance is negligible, leading
to excessive current flow.
4. What is the primary role of an insulator in an electrical system?
A. Conduct electricity
B. Provide support
C. Prevent current flow
D. Reduce voltage
Answer: C) Prevent current flow
Rationale: Insulators block the flow of electricity to enhance safety.
5. What is the role of a capacitor in a circuit?
A. Store electrical energy
B. Reduce resistance
C. Convert AC to DC
D. Measure voltage
Answer: A) Store electrical energy
Rationale: Capacitors temporarily store and release electrical energy.
, 6. The primary purpose of a ground wire is to:
A. Carry current to the load
B. Prevent electrical shock
C. Increase voltage
D. Maintain resistance
Answer: B) Prevent electrical shock
Rationale: Ground wires direct stray currents safely into the earth,
reducing shock risk.
7. The formula P=I2RP = I^2RP=I2R is used to calculate:
A. Voltage
B. Current
C. Power
D. Resistance
Answer: C) Power
Rationale: This formula calculates power based on current and
resistance.
8. Which formula represents electrical resistance?
A. R = V/I
B. R = VI
C. R = P/V
