Electrical Unit: Ultimate Practice Exam! Quiz

1. Some networks transmit and receive signals over a single wire, but most have dual wires and are commonly called "CAN-bus high (H)" and "CAN-bus low (L)," with the same message sent on both lines.

True

False

There are some situations where there is a single wire, but most networks operate on a two wire system, and the data is transmitted at two different speeds.

Explanation

There are some situations where there is a single wire, but most networks operate on a two wire system, and the data is transmitted at two different speeds.

2. Volts, amps, and ohms are the three basic units of electrical measurement.

True

False

Voltage, amperage, and resistance are the 3 main electrical measurements.

Explanation

Voltage, amperage, and resistance are the 3 main electrical measurements.

3. The _____________ monitors battery voltage and varies current flow through the rotor field circuit.

Slip rings

Rotor

Voltage regulator

Armature

The voltage regulator monitors voltage and makes adjustments based upon demand and use of the vehicle's electrical system.

Explanation

The voltage regulator monitors voltage and makes adjustments based upon demand and use of the vehicle's electrical system.

4. In calculating ohm's law:

R stands for resistance.

A stands for amps.

V stands for voltage.

All of the above

All of the above are correct.

Explanation

All of the above are correct.

5. What does DVOM stand for?

Digital volt–hour meter

Digital volt-ohmmeter

Digital valve ohmmeter

Digital variable oval meter

A DVOM is a digital volt-ohmmeter and is has that name because of what it tests and how it displays the measurement.

Explanation

A DVOM is a digital volt-ohmmeter and is has that name because of what it tests and how it displays the measurement.

6. You have a 4 ohm resister and the battery is charged to 12 volts. How many amps will flow in the circuit?

1

2

3

4

Solve volts = amps x resistance.

Explanation

Solve volts = amps x resistance.

7. The traditional automobile battery type is the:

Lead acid.

Ion.

Helium.

Nitrogen.

Lead plates and acid are the two main parts of a car battery.

Explanation

Lead plates and acid are the two main parts of a car battery.

8. When discussing a circuit, you know the voltage is 0.202 volts and the current draw is 0.00202 amp. What is the resistance in the circuit?

1

10

100

10000

Solve for ohms law. V=IR

Explanation

Solve for ohms law. V=IR

9. A technician must always wear ______________ when working on a battery.

Designer clothes

Earrings

Tennis shoes

Safety glasses

You always wear safety glasses when working in the shop, on anything.

Explanation

You always wear safety glasses when working in the shop, on anything.

10. A switch is used to:

Protect a circuit.

Allow current to flow only one way.

Reduce the current flow.

Turn current flow on and off.

A switch controls the current flow to the resistor.

Explanation

A switch controls the current flow to the resistor.

11. Tech A says you must have power supply for a simple circuit to work. Tech B says a switch will interrupt. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

The power supply is one of the components of a simple circuit. The switch interrupts the current in a circuit.

Explanation

The power supply is one of the components of a simple circuit. The switch interrupts the current in a circuit.

12. Tech A says a solenoid is not used on modern automobiles. Tech B says fuel injectors and starter motor solenoids are two of many solenoids used on modern automobiles. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Solenoids are used in many automotive applications, injectors and starter motors are 2 of these uses.

Explanation

Solenoids are used in many automotive applications, injectors and starter motors are 2 of these uses.

13. _____________ is/are fundamental to the automobile.

A 12-volt storage battery

An engine starting system

A charging system

All of the above

Are of the listed are important for a modern automobile.

Explanation

Are of the listed are important for a modern automobile.

14. Which of the following may be required when diagnosing and repairing a vehicle's electronic modules?

Software transfers

Flash reprogramming

Software updates

All of the above

Software updates, transfers, and reprogramming may all need to be performed when diagnosing or replacing a vehicle's control module.

Explanation

Software updates, transfers, and reprogramming may all need to be performed when diagnosing or replacing a vehicle's control module.

15. Controlled area network bus (CAN-bus) systems carry:

Children.

High-speed data.

Very slow data.

Info for the cruise control.

The data in a CAN is at a very high speed with respect to other data transfer in a vehicle.

Explanation

The data in a CAN is at a very high speed with respect to other data transfer in a vehicle.

16. CAN-bus is a _______-speed network.

Medium

High

Low

None of the above

Data on a CAN transmits at a high speed.

Explanation

Data on a CAN transmits at a high speed.

17. Tech A says you can calculate total circuit current with this formula I = V ÷ R. Tech B says you can determine the total voltage drop using Ohm's law. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Ohm's law is V=IR, no matter how you arrange it. You can use Ohm's law to determine the total drop of voltage.

Explanation

Ohm's law is V=IR, no matter how you arrange it. You can use Ohm's law to determine the total drop of voltage.

18. The following battery has removable cell covers.

Sealed

Maintenance free

Lead acid flooded cell

None of the above

Only the flooded cell battery has removable covers to check the internal water level.

Explanation

Only the flooded cell battery has removable covers to check the internal water level.

19. Ohm's law tells us that it takes 1 volt to push 1 amp through how many ohms?

1

2

3

4

Solve volts = amps x resistance.

Explanation

Solve volts = amps x resistance.

20. Tech A says an oscilloscope is commonly referred to as a lab scope or just scope. Tech B says lab scopes are not very important test instruments in a modern automobile. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Yes, the scope is commonly referred to as either of the three listed, and are very important instruments in testing and inspecting faults with modern automobiles.

Explanation

Yes, the scope is commonly referred to as either of the three listed, and are very important instruments in testing and inspecting faults with modern automobiles.

21. When doing a voltage drop test, you should do all these EXCEPT:

Select auto range volts DC.

Connect the red lead to volt/ohm.

Remove the positive battery cable.

Ensure the current is flowing.

If you're doing a voltage drop, you need the circuit to be live. Disconnecting the battery cable will open the circuit.

Explanation

If you're doing a voltage drop, you need the circuit to be live. Disconnecting the battery cable will open the circuit.

22. Tech A says there are three ways to check a circuit with Ohm's law. Tech B says if you know two of the measurements, Ohm's law will show you the third. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

You can check a circuit for resistance, voltage, and current. If you have two of the measurements, you will be solving for a single variable.

Explanation

You can check a circuit for resistance, voltage, and current. If you have two of the measurements, you will be solving for a single variable.

23. Tech A says wire size is very important. Tech B says there are two scales used to measure wire size. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Wire size is very important. That is why the starter cables are the size they are. There are many gauges of wire size.

Explanation

Wire size is very important. That is why the starter cables are the size they are. There are many gauges of wire size.

24. Tech A says that batteries should be disposed of in landfills. Tech B says that batteries must be recycled. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Car batteries have lead and should always be recycled.

Explanation

Car batteries have lead and should always be recycled.

25. Tech A says that the starter converts mechanical energy to electrical energy. Tech B says that the starter converts electrical energy to mechanical energy. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

The starter takes the battery's charge and converts it into movement, or mechanical energy.

Explanation

The starter takes the battery's charge and converts it into movement, or mechanical energy.

26. How many paths are there in a series circuit?

1

2

3

4

A series circuit is when the resistances are sequentially in line with each other.

Explanation

A series circuit is when the resistances are sequentially in line with each other.

27. Tech A says Ohm's law will show how many amps are needed in a circuit with 110 ohm resistor and a 12-volt power supply. The amps needed are:

12 amps.

1.2 amps.

0.12 amps.

0.012 amps.

Solve for ohms law. V=IR

Explanation

Solve for ohms law. V=IR

28. The ______________ allows current to flow one way in the rectifier assembly.

Diode

Thyroid

Electromotive force (EMF)

Counter-electromotive force (CEMF)

The diode only allows current to flow one way through the circuit.

Explanation

The diode only allows current to flow one way through the circuit.

29. Tech A says relays are turned on and off by a small amount of current. Tech B says there are two types of relays: normally closed (NC) and normally open (NO) types. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

A small amount of current is used to energize the windings in a relay. They can either be normally open or closed.

Explanation

A small amount of current is used to energize the windings in a relay. They can either be normally open or closed.

30. Tech A says most digital volt-ohmmeters (DVOMs) have both auto range and a manual range setting. Tech B says OL means overload and indicates the voltage being read is higher than the maximum. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

DVOMs have both a manual and auto setting. OL does mean you are measuring more than the maximum setting set on the meter.

Explanation

DVOMs have both a manual and auto setting. OL does mean you are measuring more than the maximum setting set on the meter.

31. Electrochemical energy is produced when:

The sun shines on photocells.

The steam builds.

When two dissimilar metals are heated.

Two dissimilar metals are immersed in an acidic liquid.

The reaction between the acid and the lead is what creates the movement of electrons.

Explanation

The reaction between the acid and the lead is what creates the movement of electrons.

32. Tech A says an alternator has to have a transformer and a rectifier is used to produce DC volts. Tech B says you can run an AC motor on DC volts. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Alternators create AC voltage and need to be rectified to DC to be used in automobiles. You can not run an AC motor on DC volts, and vise versa.

Explanation

Alternators create AC voltage and need to be rectified to DC to be used in automobiles. You can not run an AC motor on DC volts, and vise versa.

33. When calculating current flow in a parallel circuit that has 4 resistors, you would:

Divide the total current flow by the volts.

Multiply the current flow by 4.

Add the current flow for each resistor together.

Subtract the volts from amps and add 2 volts.

The sum of the resistances in a parallel circuit equals the total current flow in the circuit.

Explanation

The sum of the resistances in a parallel circuit equals the total current flow in the circuit.

34. Tech A says voltage drops can be measured as long as current is flowing. Tech B says voltage drops can be measured across components, connectors, or cables. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

You need current flow to measure a drop in voltage, and can be done across any kind of circuit or load.

Explanation

You need current flow to measure a drop in voltage, and can be done across any kind of circuit or load.

35. When doing a voltage drop test, the reading is 2.7 volts across the circuit. How many volts are going to the load?

12 volts

9.3 volts

8.3 volts

3.7 volts

The voltage drop test measures the difference in voltage across a circuit. In this case, the reading is 2.7 volts. Since the total voltage in the circuit is 12 volts, subtracting the voltage drop from the total voltage gives us the voltage going to the load. Therefore, the voltage going to the load is 9.3 volts.

Explanation

The voltage drop test measures the difference in voltage across a circuit. In this case, the reading is 2.7 volts. Since the total voltage in the circuit is 12 volts, subtracting the voltage drop from the total voltage gives us the voltage going to the load. Therefore, the voltage going to the load is 9.3 volts.

36. Tech A says when checking resistance in a circuit, you need to have power connected to the component. Tech B says ideally, you should have a component disconnected. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

A circuit does not need to be live to test for resistance. Having the component will keep from any feedback testing from happening.

Explanation

A circuit does not need to be live to test for resistance. Having the component will keep from any feedback testing from happening.

37. Tech A says copper has a low resistance. Tech B says the length of wire doesn't affect resistance. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Copper has a low resistance. That is why it is used to carry electricity. Both the length and width of a wire will effect the amount of resistance it has.

Explanation

Copper has a low resistance. That is why it is used to carry electricity. Both the length and width of a wire will effect the amount of resistance it has.

38. The process of converting alternating current (AC) into direct current (DC) is called:

Rectification.

Electromotive force (EMF).

Counter-electromotive force (CEMF).

Recertification.

The alternator rectifies the AC voltage into DC voltage.

Explanation

The alternator rectifies the AC voltage into DC voltage.

39. Tech A says checking a variable resistor is almost the same as a regular resistor. Tech B says you have to have a different type of digital volt-ohmmeter (DVOM) to read a variable resistor. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

A resistor is a resistor. There are only small differences between them. There is only one kind of DVOM.

Explanation

A resistor is a resistor. There are only small differences between them. There is only one kind of DVOM.

40. Controlled area network bus (CAN-bus) systems should be checked using a(n):

Power probe

Analog meter

Test light

Digital multimeter

CANs can be checked with either a digital multimeter or an osciliscope.

Explanation

CANs can be checked with either a digital multimeter or an osciliscope.

41. Tech A says when you ground a circuit, you hook it back to the positive side of the battery. Tech B says some manufactures use the chassis as a return path to the battery. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Grounding is the act of completing the circuit to the negative part of the battery. Since the battery ground hooks up to the chassis, it can be used as a universal ground for the vehicle.

Explanation

Grounding is the act of completing the circuit to the negative part of the battery. Since the battery ground hooks up to the chassis, it can be used as a universal ground for the vehicle.

42. When probing wires, you should do all these EXCEPT:

Back probe when possible.

Use caution when piercing wiring not to damage the wire internally.

Reinsulate the hole with room temperature vulcanizing silicone.

Never use excessive force.

Never reseal a hole after probing with silicone.

Explanation

Never reseal a hole after probing with silicone.

43. A variable resistor:

Has a fixed resistance.

Changes with the amount of voltage applied.

All of the above

Think of a fuel level sensor, also known as a sending unit.

Explanation

Think of a fuel level sensor, also known as a sending unit.

44. Tech A says when doing a voltage drop test, the voltmeter needs to be set to ohm. Tech B says current has to be flowing to do a voltage drop test. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

DVOM needs to be set to test volts, and yes, you need a live circuit to test the voltage drop.

Explanation

DVOM needs to be set to test volts, and yes, you need a live circuit to test the voltage drop.

45. Tech A says a resistor is a component designed to extract energy from the current flow. Tech B says he uses a voltmeter to check for a voltage drop. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Resistors or loads eat up the energy from the source. A voltmeter is used to measure the drop of voltage through a circuit.

Explanation

Resistors or loads eat up the energy from the source. A voltmeter is used to measure the drop of voltage through a circuit.

46. Tech A says parallel circuits are like links in a chain. Tech B says total current in a parallel circuit equals the sum of the current flowing in each branch of the circuit. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Parallel circuits are when the resistances are side by side, with individual power supplies and grounds. The sum of all of the current draws in a parallel circuit is the total current draw in the circuit.

Explanation

Parallel circuits are when the resistances are side by side, with individual power supplies and grounds. The sum of all of the current draws in a parallel circuit is the total current draw in the circuit.

47. Tech A says that failure of a battery hold down can cause battery plate damage. Tech B says that a bungee cord is a suitable battery hold down. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

The constant jarring of the battery internals will cause the lead plates to shatter. Anything other than an acceptable battery hold down is insufficient.

Explanation

The constant jarring of the battery internals will cause the lead plates to shatter. Anything other than an acceptable battery hold down is insufficient.

48. Tech A says that in a relay, current is sent through a resistor and a magnetic field is produced. Tech B says to check the amps in a circuit, you need to connect the leads parallel to the circuit. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

A relay has two sides. The control side has a winding that gets charged and closes the switch on the other side of the relay. To read amperage in a circuit, you either need an amp clamp or to hook up the DVOM in series with the circuit.

Explanation

A relay has two sides. The control side has a winding that gets charged and closes the switch on the other side of the relay. To read amperage in a circuit, you either need an amp clamp or to hook up the DVOM in series with the circuit.

49. What materials make a good insulator?

Copper and aluminum

Ceramic and plastic

Both A and B

None of the above

Ceramics, plastics and rubbers are good insulators. They do not readily accept or give electrons.

Explanation

Ceramics, plastics and rubbers are good insulators. They do not readily accept or give electrons.

50. Tech A says the CAN-bus system has a data link connector (DLC) that provides a connection into the data network and allows scan tools to connect into the network. Tech B says when there is an issue with the CAN-bus system, a diagnostic trouble code (DTC) with an "N" designation will typically be set, indicating the nature of the fault. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

The DLC is the interface between the vehicle's systems and the scan tool. U is the generic letter designation for communication faults.

Explanation

The DLC is the interface between the vehicle's systems and the scan tool. U is the generic letter designation for communication faults.

51. Tech A says an atom with more electrons than protons has an overall positive charge. Tech B says not all atoms can give up or accept electrons easily. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

The charge of electrons and protons in an atom cancel each other. Some atoms are already "happy", others want to accept electrons, and others what to give up theirs to have 8 valence electrons.

Explanation

The charge of electrons and protons in an atom cancel each other. Some atoms are already "happy", others want to accept electrons, and others what to give up theirs to have 8 valence electrons.

52. The nominal voltage of each cell of a battery is _____________ volts.

1.9

2.0

2.1

2.2

Each healthy cell in a car's battery should have 2.1 volts. 6 cells multiplied by 2.1 equals 12.6 volts.

Explanation

Each healthy cell in a car's battery should have 2.1 volts. 6 cells multiplied by 2.1 equals 12.6 volts.

53. Tech A says high resistance causes an increase in current flow. Tech B says a voltage drop is another name for high resistance. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

High resistance does not increase current flow. Solve ohms law for constant voltage and infinite resistance. The drop of voltage in a circuit is a measurement of how much resistance there is in the part of the circuit being measured.

Explanation

High resistance does not increase current flow. Solve ohms law for constant voltage and infinite resistance. The drop of voltage in a circuit is a measurement of how much resistance there is in the part of the circuit being measured.

54. Tech A says higher-speed networks are used for critical data such as supplemental restraint systems, anti-lock brake systems, and engine controls. Tech B says lower-speed networks are used for lower priority data such as data related to entertainment systems. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

We want to use a higher speed to transfer the most important data.

Explanation

We want to use a higher speed to transfer the most important data.

55. The horn switch is usually mounted in the steering wheel and requires a method to maintain an electrical connection to the circuit as the steering wheel rotates. This connection is called a:

Slot spring.

Swivel switch.

Clock spring.

Diaphragm.

The clock spring is the part the links the steering wheel electrical functions to the rest of the car.

Explanation

The clock spring is the part the links the steering wheel electrical functions to the rest of the car.

56. Tech A says that to do a quick test on an alternator charging system is to remove one of the cables off the battery posts, and if the engine continues to run, then the charging system is good. Tech B says that the practice of removing a battery cable connection can damage the electronics on the vehicle. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Removing the battery cable from the battery is an antiquated method of testing the charging system. The alternator needs to be taxed and the current observed to truly know if it is faulty.

Explanation

Removing the battery cable from the battery is an antiquated method of testing the charging system. The alternator needs to be taxed and the current observed to truly know if it is faulty.

57. When reading a digital volt-ohmmeter (DVOM), you have a reading of 2168 mV, which is the same as:

2168 millivolts.

2.168 volts.

1000 mV.

Both A and B

2168mV = 2.168 volts = 2168millivolts

Explanation

2168mV = 2.168 volts = 2168millivolts

58. Tech A says in a parallel circuit, the more branches that are added, the more current flow increases. Tech B says a series-parallel circuit is made of parallel circuits only. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

The sum of the currents in a parallel circuit equal the total draw of current. A series-parallel circuit is exactly that, a circuit with resistors in series and parallel.

Explanation

The sum of the currents in a parallel circuit equal the total draw of current. A series-parallel circuit is exactly that, a circuit with resistors in series and parallel.

59. Tech A says that the alternator converts electrical energy into mechanical energy. Tech B says that the alternator converts mechanical energy into electrical energy. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

The alternator in a vehicle is responsible for converting mechanical energy, which is generated by the engine, into electrical energy. This electrical energy is used to charge the battery and power the vehicle's electrical systems while the engine is running. Tech B is correct, while Tech A's statement is incorrect because the alternator does not convert electrical energy into mechanical energy.

Explanation

The alternator in a vehicle is responsible for converting mechanical energy, which is generated by the engine, into electrical energy. This electrical energy is used to charge the battery and power the vehicle's electrical systems while the engine is running. Tech B is correct, while Tech A's statement is incorrect because the alternator does not convert electrical energy into mechanical energy.

60. Which of the following is not a diagnostic tool used in the testing of the controlled area network bus (CAN-bus) system?

Data link connector (DLC) breakout box

Digital volt-ohmmeter

Network converter

Digital storage oscilloscope

The breakout box, DVOM, and oscilloscope are all options in diagnosing a CAN.

Explanation

The breakout box, DVOM, and oscilloscope are all options in diagnosing a CAN.

61. Tech A says that the horn circuit can fail in many ways. Any of the components in the circuit can go bad, as can the wiring. Tech B says when testing the horn, it may be easiest to first see if power is getting to the horn when it is activated, because it is not uncommon for horns to go bad, especially if they are rarely used or overused. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Anything or multiple things can go wring in an electrical circuit. Horns can go bad if rarely used or overused. Testing for power supply and ground at the horn is an easy way to test its health.

Explanation

Anything or multiple things can go wring in an electrical circuit. Horns can go bad if rarely used or overused. Testing for power supply and ground at the horn is an easy way to test its health.

62. All of the following are common automotive network configurations EXCEPT:

Bussed parallel.

Looped series.

Star parallel.

Triangle series.

CANs can not exist in the shape of a triangle.

Explanation

CANs can not exist in the shape of a triangle.

63. If only the intermittent speed setting on the windshield wipers is not working, it may be caused by a faulty:

Fuse.

Delay module.

Motor brush.

Switch.

The delay module is the only thing listed that will effect the intermittent wiper operation.

Explanation

The delay module is the only thing listed that will effect the intermittent wiper operation.

64. Tech A says testing across the battery will show you better voltage. Tech B says when checking across a switch, he has a 2-volt drop, which means only 10 volts are going to the light. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Testing from the battery directly will give you the best amount of voltage. The voltage drop is the difference of voltage in two different places in a circuit. What is left for the load is the drop amount, and its difference with battery voltage.

Explanation

Testing from the battery directly will give you the best amount of voltage. The voltage drop is the difference of voltage in two different places in a circuit. What is left for the load is the drop amount, and its difference with battery voltage.

65. What are the three types of resistors?

Rheostats, potentiometers, thermistors

Fixed, fluid, thermistors

Round, square, triangle

Thermistors, negative temperature coefficient (NTC) thermistor resistance, positive temperature coefficient (PTC) thermistor resistance

Three different types of resistors are listed in option A.

Explanation

Three different types of resistors are listed in option A.

66. On modern vehicles, what replaced the voltage regulator?

Power train control module (PCM) or body control module (BCM)

Electronic control module (ECM)

Electromotive force (EMF)

Counter-electromotive force (CEMF)

Control modules are now responsible for monitoring and adjusting current output of an alternator.

Explanation

Control modules are now responsible for monitoring and adjusting current output of an alternator.

67. Tech A says that the standard 12-volt car battery has 3 cells with 4.2 volts in each cell. Tech B says that the standard 12-volt car battery has 4 cells with 3.3 volts each. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

The standard car battery has 6 cells with 2.1 volts a piece.

Explanation

The standard car battery has 6 cells with 2.1 volts a piece.

68. Tech A says fiber optic cables are more expensive and very heavy. Tech B says fiber optics can only carry very little data. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Fiber optic cables are made from plastic. They are very light and cheap to make. Pulses of light have the ability to transfer a large amount of data, very quickly, and with very little energy used.

Explanation

Fiber optic cables are made from plastic. They are very light and cheap to make. Pulses of light have the ability to transfer a large amount of data, very quickly, and with very little energy used.

69. Tech A says AC stands for alternating voltage. Tech B says DC is used in electric motors on most hybrid vehicles. Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

AC stands for alternating current. DC stands for direct current and is not used in hybrid vehicles to run electric motors.

Explanation

AC stands for alternating current. DC stands for direct current and is not used in hybrid vehicles to run electric motors.

70. Tech A says you can measure up to 100 amps directly through the meter. Tech B says when checking high volts, you need to use a volt clamp so you don't damage the digital volt-ohmmeter (DVOM). Who is correct?

Tech A

Tech B

Both Techs A and B

Neither Tech A nor B

Most meters can't handle that much current and before measuring current, you should check the DVOM to see what it can handle. Amperage or current is measured with a clamp.

Explanation

Most meters can't handle that much current and before measuring current, you should check the DVOM to see what it can handle. Amperage or current is measured with a clamp.

Electrical Unit: Ultimate Practice Exam! Quiz

1. Some networks transmit and receive signals over a single wire, but most have dual wires and are commonly called "CAN-bus high (H)" and "CAN-bus low (L)," with the same message sent on both lines.

2.

What first name or nickname would you like us to use?

2. Volts, amps, and ohms are the three basic units of electrical measurement.

3. The _____________ monitors battery voltage and varies current flow through the rotor field circuit.

4. In calculating ohm's law:

5. What does DVOM stand for?

6. You have a 4 ohm resister and the battery is charged to 12 volts. How many amps will flow in the circuit?

7. The traditional automobile battery type is the:

8. When discussing a circuit, you know the voltage is 0.202 volts and the current draw is 0.00202 amp. What is the resistance in the circuit?

9. A technician must always wear ______________ when working on a battery.

10. A switch is used to:

11. Tech A says you must have power supply for a simple circuit to work. Tech B says a switch will interrupt. Who is correct?

12. Tech A says a solenoid is not used on modern automobiles. Tech B says fuel injectors and starter motor solenoids are two of many solenoids used on modern automobiles. Who is correct?

13. _____________ is/are fundamental to the automobile.

14. Which of the following may be required when diagnosing and repairing a vehicle's electronic modules?

15. Controlled area network bus (CAN-bus) systems carry:

16. CAN-bus is a _______-speed network.

17. Tech A says you can calculate total circuit current with this formula I = V ÷ R. Tech B says you can determine the total voltage drop using Ohm's law. Who is correct?

18. The following battery has removable cell covers.

19. Ohm's law tells us that it takes 1 volt to push 1 amp through how many ohms?

20. Tech A says an oscilloscope is commonly referred to as a lab scope or just scope. Tech B says lab scopes are not very important test instruments in a modern automobile. Who is correct?

21. When doing a voltage drop test, you should do all these EXCEPT:

22. Tech A says there are three ways to check a circuit with Ohm's law. Tech B says if you know two of the measurements, Ohm's law will show you the third. Who is correct?

23. Tech A says wire size is very important. Tech B says there are two scales used to measure wire size. Who is correct?

24. Tech A says that batteries should be disposed of in landfills. Tech B says that batteries must be recycled. Who is correct?

25. Tech A says that the starter converts mechanical energy to electrical energy. Tech B says that the starter converts electrical energy to mechanical energy. Who is correct?

26. How many paths are there in a series circuit?

27. Tech A says Ohm's law will show how many amps are needed in a circuit with 110 ohm resistor and a 12-volt power supply. The amps needed are:

28. The ______________ allows current to flow one way in the rectifier assembly.

29. Tech A says relays are turned on and off by a small amount of current. Tech B says there are two types of relays: normally closed (NC) and normally open (NO) types. Who is correct?

30. Tech A says most digital volt-ohmmeters (DVOMs) have both auto range and a manual range setting. Tech B says OL means overload and indicates the voltage being read is higher than the maximum. Who is correct?

31. Electrochemical energy is produced when:

32. Tech A says an alternator has to have a transformer and a rectifier is used to produce DC volts. Tech B says you can run an AC motor on DC volts. Who is correct?

33. When calculating current flow in a parallel circuit that has 4 resistors, you would:

34. Tech A says voltage drops can be measured as long as current is flowing. Tech B says voltage drops can be measured across components, connectors, or cables. Who is correct?

35. When doing a voltage drop test, the reading is 2.7 volts across the circuit. How many volts are going to the load?

36. Tech A says when checking resistance in a circuit, you need to have power connected to the component. Tech B says ideally, you should have a component disconnected. Who is correct?

37. Tech A says copper has a low resistance. Tech B says the length of wire doesn't affect resistance. Who is correct?

38. The process of converting alternating current (AC) into direct current (DC) is called:

39. Tech A says checking a variable resistor is almost the same as a regular resistor. Tech B says you have to have a different type of digital volt-ohmmeter (DVOM) to read a variable resistor. Who is correct?

40. Controlled area network bus (CAN-bus) systems should be checked using a(n):

41. Tech A says when you ground a circuit, you hook it back to the positive side of the battery. Tech B says some manufactures use the chassis as a return path to the battery. Who is correct?

42. When probing wires, you should do all these EXCEPT:

43. A variable resistor:

44. Tech A says when doing a voltage drop test, the voltmeter needs to be set to ohm. Tech B says current has to be flowing to do a voltage drop test. Who is correct?

45. Tech A says a resistor is a component designed to extract energy from the current flow. Tech B says he uses a voltmeter to check for a voltage drop. Who is correct?

46. Tech A says parallel circuits are like links in a chain. Tech B says total current in a parallel circuit equals the sum of the current flowing in each branch of the circuit. Who is correct?

47. Tech A says that failure of a battery hold down can cause battery plate damage. Tech B says that a bungee cord is a suitable battery hold down. Who is correct?

48. Tech A says that in a relay, current is sent through a resistor and a magnetic field is produced. Tech B says to check the amps in a circuit, you need to connect the leads parallel to the circuit. Who is correct?

49. What materials make a good insulator?

51. Tech A says an atom with more electrons than protons has an overall positive charge. Tech B says not all atoms can give up or accept electrons easily. Who is correct?

52. The nominal voltage of each cell of a battery is _____________ volts.

53. Tech A says high resistance causes an increase in current flow. Tech B says a voltage drop is another name for high resistance. Who is correct?

54. Tech A says higher-speed networks are used for critical data such as supplemental restraint systems, anti-lock brake systems, and engine controls. Tech B says lower-speed networks are used for lower priority data such as data related to entertainment systems. Who is correct?

55. The horn switch is usually mounted in the steering wheel and requires a method to maintain an electrical connection to the circuit as the steering wheel rotates. This connection is called a:

57. When reading a digital volt-ohmmeter (DVOM), you have a reading of 2168 mV, which is the same as:

58. Tech A says in a parallel circuit, the more branches that are added, the more current flow increases. Tech B says a series-parallel circuit is made of parallel circuits only. Who is correct?

59. Tech A says that the alternator converts electrical energy into mechanical energy. Tech B says that the alternator converts mechanical energy into electrical energy. Who is correct?

60. Which of the following is not a diagnostic tool used in the testing of the controlled area network bus (CAN-bus) system?

62. All of the following are common automotive network configurations EXCEPT:

63. If only the intermittent speed setting on the windshield wipers is not working, it may be caused by a faulty:

64. Tech A says testing across the battery will show you better voltage. Tech B says when checking across a switch, he has a 2-volt drop, which means only 10 volts are going to the light. Who is correct?

65. What are the three types of resistors?

66. On modern vehicles, what replaced the voltage regulator?

67. Tech A says that the standard 12-volt car battery has 3 cells with 4.2 volts in each cell. Tech B says that the standard 12-volt car battery has 4 cells with 3.3 volts each. Who is correct?

68. Tech A says fiber optic cables are more expensive and very heavy. Tech B says fiber optics can only carry very little data. Who is correct?

69. Tech A says AC stands for alternating voltage. Tech B says DC is used in electric motors on most hybrid vehicles. Who is correct?

70. Tech A says you can measure up to 100 amps directly through the meter. Tech B says when checking high volts, you need to use a volt clamp so you don't damage the digital volt-ohmmeter (DVOM). Who is correct?