Siemens Level 1 Exam |100% Correct
Questions and Verified Answers PLUS
RATIONALES| | Grade A || LATEST
UPDATE 2026
1.
Q: Ohm’s Law states that:
A) Voltage = Current × Resistance
B) Current = Voltage × Resistance
C) Power = Voltage × Resistance
D) Resistance = Voltage × Power
A: A
Rationale: Ohm’s Law: V = I × R; voltage equals current times resistance.
2.
Q: The unit of electrical current is:
A) Volt
B) Ampere
C) Ohm
D) Watt
A: B
Rationale: Current is measured in amperes (A).
3.
Q: The unit of electrical resistance is:
A) Ohm
B) Volt
C) Ampere
D) Watt
,A: A
Rationale: Resistance is measured in ohms (Ω).
4.
Q: A circuit has a voltage of 120 V and a resistance of 24 Ω. What is the current?
A) 5 A
B) 2 A
C) 12 A
D) 24 A
A: A
Rationale: Using Ohm’s Law: I = V / R → 120 ÷ 24 = 5 A.
5.
Q: Electrical power in a DC circuit is calculated by:
A) P = V × I
B) P = I / R
C) P = V / I
D) P = I × R²
A: A
Rationale: Power (watts) = voltage (V) × current (I).
6.
Q: Which device protects a circuit from overcurrent?
A) Transformer
B) Circuit breaker
C) Resistor
D) Capacitor
A: B
Rationale: Circuit breakers or fuses interrupt current if it exceeds safe limits.
7.
, Q: In AC systems, frequency is measured in:
A) Hertz
B) Volts
C) Amperes
D) Watts
A: A
Rationale: Frequency (cycles per second) is measured in hertz (Hz).
8.
Q: A three-phase system has phases A, B, and C. Which is true?
A) Each phase is 120° apart
B) All phases are 90° apart
C) They have equal voltage but different current
D) Only two phases are active
A: A
Rationale: In a three-phase system, each phase is separated by 120°.
9.
Q: Grounding a system helps:
A) Prevent electrical shock and stabilize voltage
B) Increase current
C) Reduce resistance
D) Store energy
A: A
Rationale: Grounding provides a safe path for fault current and stabilizes system voltage.
10.
Q: A transformer is used to:
A) Change voltage levels
B) Store electrical energy
C) Convert AC to DC
D) Measure current
Questions and Verified Answers PLUS
RATIONALES| | Grade A || LATEST
UPDATE 2026
1.
Q: Ohm’s Law states that:
A) Voltage = Current × Resistance
B) Current = Voltage × Resistance
C) Power = Voltage × Resistance
D) Resistance = Voltage × Power
A: A
Rationale: Ohm’s Law: V = I × R; voltage equals current times resistance.
2.
Q: The unit of electrical current is:
A) Volt
B) Ampere
C) Ohm
D) Watt
A: B
Rationale: Current is measured in amperes (A).
3.
Q: The unit of electrical resistance is:
A) Ohm
B) Volt
C) Ampere
D) Watt
,A: A
Rationale: Resistance is measured in ohms (Ω).
4.
Q: A circuit has a voltage of 120 V and a resistance of 24 Ω. What is the current?
A) 5 A
B) 2 A
C) 12 A
D) 24 A
A: A
Rationale: Using Ohm’s Law: I = V / R → 120 ÷ 24 = 5 A.
5.
Q: Electrical power in a DC circuit is calculated by:
A) P = V × I
B) P = I / R
C) P = V / I
D) P = I × R²
A: A
Rationale: Power (watts) = voltage (V) × current (I).
6.
Q: Which device protects a circuit from overcurrent?
A) Transformer
B) Circuit breaker
C) Resistor
D) Capacitor
A: B
Rationale: Circuit breakers or fuses interrupt current if it exceeds safe limits.
7.
, Q: In AC systems, frequency is measured in:
A) Hertz
B) Volts
C) Amperes
D) Watts
A: A
Rationale: Frequency (cycles per second) is measured in hertz (Hz).
8.
Q: A three-phase system has phases A, B, and C. Which is true?
A) Each phase is 120° apart
B) All phases are 90° apart
C) They have equal voltage but different current
D) Only two phases are active
A: A
Rationale: In a three-phase system, each phase is separated by 120°.
9.
Q: Grounding a system helps:
A) Prevent electrical shock and stabilize voltage
B) Increase current
C) Reduce resistance
D) Store energy
A: A
Rationale: Grounding provides a safe path for fault current and stabilizes system voltage.
10.
Q: A transformer is used to:
A) Change voltage levels
B) Store electrical energy
C) Convert AC to DC
D) Measure current
