LADWP Electric Station
Operator Exam Practice
Questions And Correct
Answers (Verified Answers)
Plus Rationale 2027 Q&A|
Instant Download Pdf.
1. What is the basic unit of electrical resistance?
A. Volt
B. Ampere
C. Ohm
D. Watt
Resistance is measured in ohms (Ω).
2. Which instrument is normally used to measure current?
A. Voltmeter
B. Ammeter
C. Megohmmeter
D. Wattmeter
An ammeter measures current in amperes.
3. Ohm's Law is expressed as:
A. P = VI
B. I = PR
,C. V = IR
D. R = VI
Ohm's Law states that voltage equals current multiplied by
resistance.
4. A 120-V circuit has a resistance of 20 Ω. What current flows?
A. 2 A
B. 4 A
C. 6 A
D. 10 A
I = V/R = 120/20 = 6 A.
5. Electrical power is commonly measured in:
A. Ohms
B. Amperes
C. Volts
D. Watts
The watt is the standard unit of electrical power.
6. Which equation calculates DC electrical power?
A. P = I/R
B. P = V/R
C. P = VI
D. P = R/V
Power equals voltage multiplied by current.
7. What happens to current in a series circuit if resistance increases
while voltage remains constant?
A. It increases
B. It decreases
C. It remains constant
D. It becomes zero immediately
,By Ohm's Law, increasing resistance reduces current for a fixed
voltage.
8. In a parallel circuit, the voltage across each ideal branch is:
A. Different in every branch
B. Zero
C. Half the source voltage
D. Equal to the source voltage
Parallel branches share the same two electrical nodes.
9. What is the primary function of a transformer?
A. Store electrical energy
B. Convert AC to DC
C. Change AC voltage and current levels
D. Increase frequency
Transformers transfer AC energy between circuits while changing
voltage/current levels.
10. A transformer that increases voltage is called a:
A. Step-down transformer
B. Isolation transformer
C. Step-up transformer
D. Current transformer
A step-up transformer raises voltage while ideally reducing current
proportionally.
11. What is the frequency of a standard North American utility AC
system?
A. 25 Hz
B. 50 Hz
C. 60 Hz
D. 120 Hz
, North American power systems commonly operate at 60 Hz.
12. What does AC stand for?
A. Automatic Control
B. Applied Current
C. Alternating Current
D. Auxiliary Circuit
Alternating current periodically changes direction.
13. What does DC stand for?
A. Direct Control
B. Direct Current
C. Distribution Current
D. Differential Current
Direct current flows in one direction.
14. Which material is generally an excellent electrical conductor?
A. Rubber
B. Glass
C. Plastic
D. Copper
Copper has high electrical conductivity and is widely used for
conductors.
15. What is the purpose of electrical insulation?
A. Increase current
B. Increase frequency
C. Prevent unwanted current flow
D. Increase conductor temperature
Insulation separates energized conductors from people and other
conductive surfaces.
Operator Exam Practice
Questions And Correct
Answers (Verified Answers)
Plus Rationale 2027 Q&A|
Instant Download Pdf.
1. What is the basic unit of electrical resistance?
A. Volt
B. Ampere
C. Ohm
D. Watt
Resistance is measured in ohms (Ω).
2. Which instrument is normally used to measure current?
A. Voltmeter
B. Ammeter
C. Megohmmeter
D. Wattmeter
An ammeter measures current in amperes.
3. Ohm's Law is expressed as:
A. P = VI
B. I = PR
,C. V = IR
D. R = VI
Ohm's Law states that voltage equals current multiplied by
resistance.
4. A 120-V circuit has a resistance of 20 Ω. What current flows?
A. 2 A
B. 4 A
C. 6 A
D. 10 A
I = V/R = 120/20 = 6 A.
5. Electrical power is commonly measured in:
A. Ohms
B. Amperes
C. Volts
D. Watts
The watt is the standard unit of electrical power.
6. Which equation calculates DC electrical power?
A. P = I/R
B. P = V/R
C. P = VI
D. P = R/V
Power equals voltage multiplied by current.
7. What happens to current in a series circuit if resistance increases
while voltage remains constant?
A. It increases
B. It decreases
C. It remains constant
D. It becomes zero immediately
,By Ohm's Law, increasing resistance reduces current for a fixed
voltage.
8. In a parallel circuit, the voltage across each ideal branch is:
A. Different in every branch
B. Zero
C. Half the source voltage
D. Equal to the source voltage
Parallel branches share the same two electrical nodes.
9. What is the primary function of a transformer?
A. Store electrical energy
B. Convert AC to DC
C. Change AC voltage and current levels
D. Increase frequency
Transformers transfer AC energy between circuits while changing
voltage/current levels.
10. A transformer that increases voltage is called a:
A. Step-down transformer
B. Isolation transformer
C. Step-up transformer
D. Current transformer
A step-up transformer raises voltage while ideally reducing current
proportionally.
11. What is the frequency of a standard North American utility AC
system?
A. 25 Hz
B. 50 Hz
C. 60 Hz
D. 120 Hz
, North American power systems commonly operate at 60 Hz.
12. What does AC stand for?
A. Automatic Control
B. Applied Current
C. Alternating Current
D. Auxiliary Circuit
Alternating current periodically changes direction.
13. What does DC stand for?
A. Direct Control
B. Direct Current
C. Distribution Current
D. Differential Current
Direct current flows in one direction.
14. Which material is generally an excellent electrical conductor?
A. Rubber
B. Glass
C. Plastic
D. Copper
Copper has high electrical conductivity and is widely used for
conductors.
15. What is the purpose of electrical insulation?
A. Increase current
B. Increase frequency
C. Prevent unwanted current flow
D. Increase conductor temperature
Insulation separates energized conductors from people and other
conductive surfaces.