Electrician Quiz
Questions: 16 · 10 minutes
1. Before servicing equipment, what is the central purpose of a lockout/tagout procedure?
To identify the circuit’s normal operating current
To test insulation resistance while the equipment runs
To reduce energy use during maintenance
To control hazardous energy and prevent unexpected energization or startup
2. Which unit measures the rate at which electrical energy is transferred or used?
Ampere
Volt
Watt
Ohm
3. When choosing a conductor, which term describes the maximum current it can carry continuously under specified conditions without exceeding its temperature rating?
Impedance
Polarity
Ampacity
Inductance
4. In a control diagram, what does a normally open contact do while it is in its normal, unactuated state?
It provides a closed current path
It interrupts the current path
It limits current like a resistor
It converts alternating current to direct current
5. Which unit measures opposition to the flow of electric current?
Farad
Ohm
Henry
Coulomb
6. A ground-fault circuit interrupter primarily detects a problem by comparing which quantities?
The current leaving on one conductor with the current returning on another
The supply voltage with the circuit rating
The conductor resistance with the load resistance
The real power with the apparent power
7. An AC supply is labeled 60 Hz. What does the frequency value describe?
Sixty alternating-current cycles per second
A potential difference of 60 volts
A maximum current of 60 amperes
A resistance of 60 ohms per conductor
8. Which term means the electrical potential difference between two points?
Current
Voltage
Resistance
Conductance
9. Which SI unit is used to measure electric current?
Volt
Ohm
Ampere
Watt
10. A breaker trips immediately whenever a particular appliance is switched on. Which fault most directly describes an unintended very-low-resistance path causing a large current?
Short circuit
Open circuit
Voltage drop
Power-factor correction
11. In an ideal step-down transformer, the secondary voltage decreases. If power is treated as unchanged, what happens to the available secondary current?
It remains equal to the primary current in every case
It falls to zero
It increases
It changes into direct current
12. What is the primary function of an equipment grounding conductor during a fault?
To carry the load’s normal operating current
To increase resistance so the fault current remains small
To regulate the circuit’s normal voltage
To provide a low-impedance fault-current path that helps a protective device operate
13. Several lamps are connected in parallel. One lamp develops an open circuit. What normally happens to the other branches?
Their currents must all fall to zero
They become connected in series
Their branch voltages double
They can continue operating because they have separate current paths
14. A resistive load draws 10 A from a 120 V supply. Approximately how much power does it use?
12 W
12,000 W
120 W
1,200 W
15. On a verified de-energized circuit, a continuity tester indicates very low resistance between two ends of a conductor. What does this usually suggest?
The conductor is energized at full voltage
There is a continuous conductive path between the test points
The conductor has infinite resistance
The conductor is necessarily connected to ground
16. Three resistors of 2 Ω, 3 Ω, and 5 Ω are connected in series. What is their total resistance?
10 Ω
5 Ω
3 Ω
1 Ω