Basic Electricity for HVAC Technicians: Quizzes and Practice Tests

Question 1

Which property below is NOT a fundamental property of electricity?

Accepted Answer

Temperature

Answer

Voltage

Answer

Current

Answer

Resistance

Question 2

In a series circuit, the total resistance is:

Accepted Answer

Equal to the sum of individual resistances

Answer

Greater than the sum of individual resistances

Answer

Less than the sum of individual resistances

Answer

Dependent on the current flowing through the circuit

Question 3

Which type of electrical component stores energy in a magnetic field?

Accepted Answer

Inductor

Answer

Resistor

Answer

Capacitor

Answer

Transistor

Question 4

What is the primary purpose of a wiring diagram in an electrical system?

Accepted Answer

To provide a visual representation of the system for troubleshooting and maintenance

Answer

To calculate the electrical load of a system

Answer

To troubleshoot electrical faults

Answer

To determine the voltage and current requirements of a system

Question 5

What is the main function of a transformer in an HVAC system?

Accepted Answer

To regulate the voltage in the system

Answer

To convert AC voltage to DC voltage

Answer

To convert DC voltage to AC voltage

Answer

To provide isolation between circuits

Question 6

What is the resistance of an open circuit?

Accepted Answer

Infinite ohms

Answer

Zero ohms

Answer

Equal to the source voltage

Answer

Dependent on the type of circuit

Question 7

Which of the following is a unit of electrical power?

Accepted Answer

Watt

Answer

Ohm

Answer

Ampere

Answer

Volt

Question 8

Which unit is used to measure electrical resistance?

Accepted Answer

Ohm

Answer

Volt

Answer

Ampere

Answer

Watt

Question 9

Which type of electrical circuit allows current to flow in only one direction?

Accepted Answer

Direct current (DC) circuit

Answer

Series circuit

Answer

Parallel circuit

Answer

Alternating current (AC) circuit

Question 10

Which safety precaution is essential when working with electricity?

Accepted Answer

Use insulated tools.

Answer

Wear loose clothing.

Answer

Stand on a wet floor.

Answer

Touch electrical wires with bare hands.

Question 11

What formula is used to calculate voltage in a circuit?

Accepted Answer

Voltage = Current × Resistance

Answer

Voltage = Power × Current

Answer

Voltage = Resistance × Power

Answer

Voltage = Current ÷ Resistance

Question 12

Which type of wiring is commonly used in residential electrical systems?

Accepted Answer

Romex wiring

Answer

Conduit wiring

Answer

Knob-and-tube wiring

Answer

BX cable

Question 13

What is the primary function of a transformer in an HVAC system?

Accepted Answer

To increase or decrease voltage

Answer

To convert AC to DC

Answer

To store electrical energy

Answer

To protect against electrical shocks

Question 14

Which of the following is the SI unit of measurement for electrical current?

Accepted Answer

Amperes

Answer

Volts

Answer

Ohms

Answer

Watts

Question 15

What type of circuit is formed when multiple resistors are connected in such a way that the same current passes through each resistor?

Accepted Answer

Series circuit

Answer

Parallel circuit

Answer

Closed circuit

Answer

Open circuit

Question 16

Which of the following tools is used to accurately measure electrical resistance?

Accepted Answer

Ohmmeter

Answer

Multimeter

Answer

Ammeter

Answer

Voltmeter

Question 17

What is the primary purpose of a fuse in an electrical circuit?

Accepted Answer

To protect the circuit from excessive current

Answer

To regulate voltage

Answer

To store electrical energy

Answer

To isolate faulty components

Question 18

What is the main function of a transformer in an HVAC system?

Accepted Answer

To increase or decrease voltage

Answer

To convert AC to DC

Answer

To regulate current

Answer

To store energy

Question 19

Which type of electrical motor is commonly utilized in HVAC blowers?

Accepted Answer

AC induction motor

Answer

DC motor

Answer

Stepper motor

Answer

Servo motor

Question 20

What is the purpose of a capacitor in an HVAC system?

Accepted Answer

To enhance power factor

Answer

To store electrical energy

Answer

To reduce noise

Answer

To isolate circuits

Question 21

In an electrical circuit, which component primarily regulates the flow of current?

Accepted Answer

Resistor

Answer

Capacitor

Answer

Inductor

Answer

Battery

Question 22

Which unit of measurement is used to express electrical resistance?

Accepted Answer

Ohm

Answer

Ampere

Answer

Volt

Answer

Watt

Question 23

Which tool is specifically designed to measure electrical current?

Accepted Answer

Ammeter

Answer

Multimeter

Answer

Voltmeter

Answer

Ohmmeter

Question 24

When does a short circuit typically occur in an electrical circuit?

Accepted Answer

When current takes an unintended path

Answer

When voltage significantly decreases

Answer

When resistance increases

Answer

When the circuit is open

Question 25

In an electrical circuit, which color code is typically assigned to the neutral conductor?

Accepted Answer

White

Answer

Black

Answer

Red

Answer

Green

Question 26

What is the primary purpose of an electrical capacitor?

Accepted Answer

Storing electrical energy

Answer

Regulating current flow

Answer

Measuring voltage

Answer

Converting alternating current (AC) to direct current (DC)

Question 27

Which of the following is not a recognized type of electrical circuit configuration?

Accepted Answer

Radial circuit

Answer

Series circuit

Answer

Parallel circuit

Answer

Combination circuit

Question 28

Which property is NOT fundamental to electrical circuits?

Accepted Answer

Friction

Answer

Voltage

Answer

Current

Answer

Resistance

Question 29

In electrical circuits, what unit is used to measure current?

Accepted Answer

Ampere

Answer

Volt

Answer

Ohm

Answer

Coulomb

Question 30

Which type of wiring diagram shows the physical layout of electrical components?

Accepted Answer

Layout diagram

Answer

Schematic diagram

Answer

Wiring diagram

Question 31

Which instrument is used to measure electrical voltage?

Accepted Answer

Voltmeter

Answer

Ohmmeter

Answer

Ammeter

Question 32

What is the primary function of a fuse in an electrical circuit?

Accepted Answer

To protect against excessive current

Answer

To isolate faulty components

Answer

To regulate voltage

Question 33

What is the primary function of a capacitor in an electrical circuit?

Accepted Answer

To store electrical energy

Answer

To block AC currents

Answer

To amplify voltage

Question 34

Which component of an electrical circuit provides a path for electrons to flow?

Accepted Answer

Conductor

Answer

Source

Answer

Load

Answer

Insulator

Question 35

What is the primary function of a fuse in an electrical circuit?

Accepted Answer

To protect against overcurrent

Answer

To regulate voltage

Answer

To provide electrical isolation

Answer

To prevent grounding

Question 36

Which property is characteristic of alternating current (AC)?

Accepted Answer

Constant frequency

Answer

Constant direction of flow

Answer

Zero average value

Answer

Low voltage

Question 37

What is the mathematical formula for calculating electrical power?

Accepted Answer

Voltage multiplied by Current

Answer

Current divided by Resistance

Answer

Voltage divided by Resistance

Answer

Power multiplied by Time

Question 38

Which type of wiring method is most commonly used in residential buildings?

Accepted Answer

Romex

Answer

Conduit

Answer

BX cable

Answer

Wiremold

Question 39

What is the primary purpose of a transformer in an HVAC system?

Accepted Answer

To increase or decrease voltage

Answer

To convert AC to DC

Answer

To isolate circuits from each other

Answer

To power motors

Question 40

In an electrical circuit, which component primarily limits the flow of current?

Accepted Answer

Resistor

Answer

Capacitor

Answer

Inductor

Answer

Transistor

Question 41

Which type of wiring diagram illustrates the physical locations and connections of electrical components?

Accepted Answer

Wiring diagram

Answer

One-line diagram

Answer

Schematic diagram

Answer

Circuit diagram

Question 42

Ohm's Law establishes the direct proportionality between voltage and the product of which two circuit parameters?

Accepted Answer

Current and resistance

Answer

Current only

Answer

Resistance only

Answer

Voltage and power

Question 43

Which tool is specifically designed to measure electrical current?

Accepted Answer

Ammeter

Answer

Voltmeter

Answer

Ohmmeter

Answer

Multimeter

Question 44

During electrical troubleshooting, which step involves identifying and separating the faulty component from the rest of the circuit?

Accepted Answer

Isolation

Answer

Symptom identification

Answer

Verification

Answer

Troubleshooting

Question 45

Which type of capacitor is commonly used for long-term charge storage due to its ability to maintain a charge over extended periods?

Accepted Answer

Electrolytic capacitor

Answer

Ceramic capacitor

Answer

Tantalum capacitor

Answer

Film capacitor

Question 46

What is the purpose of a fuse in an electrical circuit?

Accepted Answer

To interrupt current flow when it exceeds a predetermined level

Answer

To allow unrestricted current flow

Answer

To regulate voltage levels

Answer

To store electrical energy

Question 47

Which of the following is not a commonly used type of electrical wiring?

Accepted Answer

PEX

Answer

Romex

Answer

Conduit

Answer

Coaxial

Question 48

Which law describes the relationship between voltage, current, and resistance in an electrical circuit?

Accepted Answer

Ohm's Law

Answer

Joule's Law

Answer

Kirchhoff's Voltage Law

Answer

Lenz's Law

Question 49

What is the SI unit of electrical current?

Accepted Answer

Ampere

Answer

Watt

Answer

Ohm

Answer

Volt

Question 50

What is the primary purpose of a fuse in an electrical circuit?

Accepted Answer

To protect the circuit from excessive current

Answer

To amplify current

Answer

To regulate voltage

Answer

To act as a switch

Question 51

What is the key difference between alternating current (AC) and direct current (DC)?

Accepted Answer

AC periodically changes direction while DC flows in one direction only.

Answer

AC has a higher voltage than DC.

Answer

DC is more dangerous than AC.

Question 52

What is the primary function of a transformer in an HVAC system?

Accepted Answer

To alter the voltage of the electrical supply

Answer

To protect the compressor

Answer

To regulate current flow

Question 53

According to electrical wire color coding, which color is typically used for the neutral wire?

Accepted Answer

White

Answer

Black

Answer

Green

Answer

Red

Question 54

What is the main purpose of a capacitor in an electrical circuit?

Accepted Answer

To store electrical energy

Answer

To regulate voltage

Answer

To protect against overcurrent

Question 55

What is the primary function of a contactor in an HVAC system?

Accepted Answer

To control the flow of electrical power to the compressor

Answer

To protect against overcurrent

Answer

To regulate fan speed

Answer

To filter out impurities

Question 56

What is the primary function of a thermostat in an HVAC system?

Accepted Answer

To regulate the temperature of a space

Answer

To protect against overcurrent

Answer

To control fan speed

Answer

To filter out impurities

Question 57

Which safety precaution is crucial to take before working on any electrical circuit?

Accepted Answer

Turn off the power supply

Answer

Call a qualified electrician

Answer

Wear gloves

Answer

Use a multimeter