chapter 36 to 37 knowledge check

A typical incandescent light bulb creates light, but only about _____ of the electricity is converted to light. A. 10% B. 20% C. 30% D. 40%

A. 10%

_____ is achieved when an electrical circuit has a continuous and uninterrupted electrical connection and is thereby capable of conducting current and working as designed. A. Continuity B. Voltage drop C. High resistance D. Openness

A. Continuity

Atoms that lose ______ become positively charged. A. Electrons B. Neutrons C. Protons D. Ions

A. Electrons

The number of charge carriers, either an excess of ________ or a deficiency of electrons (causing holes in a material), can be altered by doping, or adding very small quantities of impurities to a semiconductor material. A. Electrons B. Protons C. Neutrons D. Nuclei

A. Electrons

Electricity can perform work if it is directed at objects that can _______ the moving particles, such as lights and electric motors. A. Extract energy from B. Provide energy to C. Both A and B D. None of the above

A. Extract energy from

A _____ will contain a small electromagnetic coil using very _____ wire, whereas a _____ uses _____ wire in larger coils. A. Fuel injector; fine; starter motor; heavy B. Starter motor; fine; fuel injector; heavy C. Fuel injector; heavy; starter motor; fine D. Starter motor; heavy; fuel injector; fine Check

A. Fuel injector; fine; starter motor; heavy

When two ______ are brought close enough together, electrons leap across the gap, causing a spark and canceling out the charge imbalance. A. Insulators B. Dissimilar metals C. Broken down chemicals D. Semiconducting materials

A. Insulators

Electrolysis is when chemicals break down into charged particles, called ____. A. Ions B. Protons C. Neutrons D. Electrons

A. Ions

Alternators use ______ to create current flow to charge the battery and run the electrical accessories. A. Direct current B. Alternating current C. Polarity D. Power windings

B. Alternating current

The _____ is the unit used to describe how much current or how many electrons are flowing at a given point in a given amount of time when work is being performed—for example, when a lamp is operating. A. Volt B. Ampere C. Ohm D. None of the above

B. Ampere

Unlike charges attract, so the ________ are attracted toward the positive protons in the positive side of the battery. A. Neutrons B. Electrons C. Protons D. Nuclei

B. Electrons

With equal numbers of protons and ________, the charges within an atom cancel each other out, leaving the atom with no overall charge. A. Neutrons B. Electrons C. Nuclei D. Particles

B. Electrons

In developing engine designs, manufacturers use thermocouples to measure the ___________ of components, such as spark plugs and exhaust systems. A. High pressures B. High temperatures C. Level of wear D. None of the above

B. High temperatures

Every atom has a _________, with at least one positively charged _____ and, in most atoms, at least one _____ that has no charge. A. Nucleus; neutron; proton B. Nucleus; proton; neutron C. Proton; nucleus; neutron D. Proton; neutron; nucleus

B. Nucleus; proton; neutron

Electricity is made up of ________ they cannot be seen. A. Waves that travel through the air, so B. Tangible objects, though C. Both A and B D. Neither A nor B

B. Tangible objects, though

As hydrocarbons become _____________, the increased use of sophisticated electrical and electronic systems in vehicles to improve efficiency and economy will continue into the future. A. Scarcer B. More expensive C. More cost-effective D. Both A and B

Both A and B

Headlights transform the energy into intense heat that then makes the _____. A. Bulb filaments glow white hot B. Bulb filaments produce light C. Both A and B D. None of the above

C. Both A and B

When two ______ are immersed in an acidic liquid called an electrolyte, the breakdown of chemicals results in a flow of electricity. A. Spark plugs B. Insulators C. Dissimilar metals D. None of the above

C. Dissimilar metals

Ions are ______ charged atoms or groups of atoms. A. Positively B. Negatively C. Electrically D. Not

C. Electrically

While all materials have some resistance to current flow based on the number of ________ the material has, a resistor is a component designed to extract energy from the current flow by forcing it through a restriction in the circuit. A. Protons B. Neutrons C. Free electrons D. Temperature changes

C. Free electrons

A semiconductor's electrical resistance is ______ than that of most conductors, but ______ than that of most insulators. A. Lower; higher B. Higher; equal C. Higher; lower D. Lower; equal

C. Higher; lower

The ______ is the unit used to describe the amount of electrical resistance in a circuit or component. A. Volt B. Ampere C. Ohm D. None of the above

C. Ohm

Which of the following is NOT a factor that determines the level of electrical resistance? A. Type of material B. Length of the conductor C. Size of the depletion layer D. Diameter of the conductor

C. Size of the depletion layer

The amount of induction is dependent upon all of the following EXCEPT ____. A. The number of windings B. The speed of the movement C. The number of magnets used D. The relative distance between the field and the winding Check

C. The number of magnets used

Electricity can be produced by _____. A. The movement of a conductor through a magnetic field B. The application of pressure to a special type of crystal C. The conversion of sunlight by solar cells D. All of the above

D. All of the above

Electromagnetic induction is applied in _____. A. Alternators B. Ignition coils C. Some sensors on the vehicle D. All of the above

D. All of the above

The best-known simple application of piezoelectric energy is the sparking lighters that ignite gas in grills, barbecues, or cooktops, but the piezoelectric principle is also used in automobiles in _____. A. Knock sensors B. Pressure sensors C. Some electronic fuel injectors D. All of the above

D. All of the above

Which of the following is an effect of the flow of electricity? A. Light B. Magnetism C. Heat D. All of the above

D. All of the above

________, or current flow, can be thought of as a faucet being turned on and water flowing. A. Circuit flow B. Electrical resistance C. Voltage D. Amperage

D. Amperage

A faulty circuit may have_______. A. Continuity B. High resistance C. No continuity D. Both B and C

D. Both B and C

LEDs, which are now replacing traditional bulbs as lighting sources, produce _____ light with less heat loss, using much less energy. A. Less B. As much C. More D. Both B and C

D. Both B and C

A(n) ________ is used to measure the amount of resistance in a component or circuit. A. Hertz meter B. Voltmeter C. Ammeter D. Ohmmeter

D. Ohmmeter

When sunlight is absorbed by semiconducting materials, the ______ knock _______ loose from their atoms, causing the electrons to flow through the material to produce electricity. A. Electrons; photons B. Electrons; neutrons C. Neutrons; electrons D. Photons; electrons

D. Photons; electrons

When negative ions in a solution are attracted to the ______ plate, and positive ions to the _____ plate, a chemical reaction can occur. A. Negative; negative B. Positive; positive C. Negative; positive D. Positive; negative

D. Positive; negative

Under most conditions, except ________ change, the resistance of an object is a constant and does not depend on the amount of the voltage or the amount of current passing through it. A. Material B. Length C. Diameter D. Temperature

D. Temperature

An atom with more electrons than protons has an overall positive charge and is called a positive ion. True False

False

As current flows through motor vehicle circuits, most of the electrical energy is transformed into heat energy. True False

False

Atoms that gain electrons become positively charged. True False

False

Checking the circuit for continuity will always determine all electrical faults. True False

False

Electricity is not governed by the laws of physics. True False

False

Hertz is the measurement of frequency and indicates the number of cycles per minute. True False

False

Regardless of the way it is produced, electricity is always the movement of protons in a conducting circuit. True False

False

The characteristics of AC are the fixed polarity of the applied voltage and the flow of charges in only one direction True False

False

The depletion layer is very thick and acts like an insulator. True False

False

The strength of the magnetic field produced is not determined by the number of turns, or coils, but instead by the value of the current flow through the conductor. True False

False

A common and easily observable source of electricity is the static electricity produced in thunderstorms. True False

True

A potential electrical difference across the crystal will physically distort the crystal. True False

True

All materials have resistance—even good conductors. True False

True

Atoms with fewer electrons in the valence ring are the best conductors, with one electron being the best conductive material. True False

True

Automotive applications such as electronic control units mostly use semiconductors such as diodes, transistors, and power transistors. True False

True

Current flowing in the conductors of a generator produces heat as a by-product and is wasted energy. True False

True

Freed electrons can be made to flow in a circuit, where they are used to perform work. True False

True

Generally, three-phase motors or alternators produce more output than single-phase motors or alternators because they can maintain a much more even voltage compared to single-phase AC. True False

True

If the wire is wound into a coil, the magnetic fields combine to create a stronger and denser magnetic field, with a north and a south pole, just like a permanent magnet. True False

True

Materials made up of atoms with one to three valance ring electrons are considered conductors. True False

True

Most electronic components combine P-type and N-type semiconductors. True False

True

Pilots in general aviation use thermocouples to measure the exhaust gas temperature to adjust the fuel mixture as the airplane changes altitude. True False

True

Sometimes we need to create heat, such as in circuit breakers and heaters. True False

True

Static electricity applies to any charged surfaces where the imbalance in charge is great enough to make the electrons leap the gap. True False

True

The LED is a semiconductor diode that creates light by emitting photons from its PN junction when a current flows through it. True False

True

The higher the resistance, the less current (amps) that will flow in the circuit for any particular voltage. True False

True

The larger the charge between the negative and the positive terminal, the more strongly the positive terminal attracts and the negative terminal repels the free electrons. True False

True

The low-resistance fault causes abnormally high current flow in the circuit and may cause the circuit protection devices, such as fuses or circuit breakers, to open the circuit. True False

True

The power source pushes a flow of electrons (current flow), measured in amps, when the switch is in the closed position, completing the path. True False

True

This process of converting light (photons) to electricity (voltage, which moves electrons) is called the photovoltaic (PV) effect. True False

True

To work on current and future vehicles, it is increasingly important for the technician to have a sound understanding of electrical terminology, the behavior of electricity, and electrical component and circuit theory. True False

True