AC/DC Final

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____ states that current flows from the most positive point in a circuit to the most negative.

The conventional current flow theory

____ states that since electrons are negative particles, current flows from the most negative point in the circuit to the most positive.

The electron theory

When using Fleming's generator rule, the thumb points in the direction of the ____.

Thrust

According to the general voltage divider formula, the voltage drop across any particular resistance is equal to the total circuit current ____ the value of that resistor.

Times

______________ indicates the plus and minus limits of a resistor's ohmic value.

Tolerance

A ____________________ resistor is a resistor whose values can be changed or varied over a range

Variable

A potentiometer is a variable resistor used to provide a variable ____.

Voltage

The induced _______ is proportional to the rate of change of current

Voltage

___ push current through a wire but cannot flow through the wire

Voltage

___________ is the force that pushes the electrons through a resistance.

Voltage

_________________ is defined as electromotive force

Voltage

in a series circuit, the sum of all the voltage drops across all the resistors must be equal to the ________ applied to the circuit.

Voltage

A principal function of resistors is to produce a ____, which is used to create the different ranges in multirange voltmeters.

Voltage Divider

____ are used to provide different voltages between certain points of a circuit

Voltage Dividers

_______ can be determined by observing the direction of current flow through the circuit.

Voltage Polarity

The ____ across any branch of a parallel circuit is the same as the applied voltage.

Voltage drop

____ indicates the amount of voltage necessary to push the current through the limiting element.

Voltage drop

Electrical energy must be changed or converted into some other form of energy before there can be ____.

Wattage

____ is a measure of the amount of power being used in a circuit

Wattage

____ resistors are fixed resistors that are made by winding a piece of resistive wire around a ceramic core.

Wire Wound

resistors can operate at higher temperatures than any other type of resistor

Wire wound

Which of the following would be considered a good electrical insulator?

Wood

A ____ is the amount of force required to raise a one-pound weight one foot

foot-pound

If a series circuit has three resistors and two amps flow through each resistor, the total amperage for the circuit is ____ amps.

2

If four resistors, each with a value of 100 ohms, are connected in parallel, the total resistance of the circuit is ____ ohms.

25

A potentiometer is a variable resistor with ____ terminals.

3

Resistors that have a tolerance of plus/minus 20% have ____ color bands.

3

The maximum number of electrons that can be contained in any orbit is ____.

32

The circuit has 3 three hundred ohm resistors in parallel with each other and are in series with a 100 ohm resistor. The total circuit is 2 amps. What is the total voltage and resistance

400 volts and 200 ohms

A series circuit has individual resistor values of 200 ohms, 150 ohms, 50 ohms, and 75 ohms. The total resistance of the circuit is _________ ohms.

475

The exponential curve describes a rate of certain occurrences and is divided into ____ time constraints.

5

The value of 5 M-ohms is ____ ohms

5,000,000

Three resistors, with values of 10 ohms, 20 ohms, and 30 ohms, are connected in parallel and the circuit has a voltage of 120 volts with an amperage of 22 amps. The total current of the 20-ohm branch is ____ amps.

6

If a parallel circuit has two resistors with values of 10 ohms and 25 ohms, the total resistance of the circuit is ____ ohms.

7.14

The amount of electrical energy needed to produce one horsepower is ____ watts.

746

The ground point that is made by physically driving an object, such as a ground rod, into the ground is called a(n) ________ ground.

Earth

The Greeks called amber ____, because of its ability to attract lightweight materials when rubbed with different materials

Elektron

A(n) ____ is a substance that cannot be chemically divided into a simpler substance.

Element

A large amount of voltage that exists for a short period of time is called a peak.

False

In a AC circuit the magnetic field builds up and collapses only when the current is turned on and off.

False

In an AC circuit the magnetic field builds up and collapses only when the current is turned off and on?

False

Induction only occurs when a magnetic field collapses

False

The purpose of a transformer is to decrease or increase current.

False

A(n) ____________________ is the unit of resistance to current flow.

Ohm

The unit of measure for resistance is ____________________.

Ohms

In its simplest form, ____________________ states that it takes one volt to push one amp through one ohm.

Ohms Law

Given the voltage and the resistance, the amount of current flow in a circuit can be determined by using __________.

Ohms law

In magnetic measurement 100,000,000 lines of magnetic flux are equal to

One Weber

A ____ circuit has more than one path for current flow

Parallel

In a ____ circuit, the total current is the sum of the current through all of the circuit paths.

Parallel

In a ____ circuit, the voltage across any circuit branch is the same as the total voltage

Parallel

The total resistance of a ____ circuit is always less than the resistance of the lowest value resistor in the circuit.

Parallel

The total resistance of a _______ circuit is the reciprocal of the sum of the reciprocals of the individual branches

Parallel

________ circuits are probably the type of circuit with which most people are familiar, such as when working with lights and receptacles in homes and office building

Parallel

A section of a combination circuit composed of parallel resistors is called

Parallel Block

One function of ____________________ is to limit the flow of current through a circuit.

Resistor

A rheostat is a variable resistor with ____ terminals

2

The circuit has two 300 ohm resistors in parallel with each other which are in series with a 600 ohm and a 400 ohm resistor. Vs=10volts. What is the totoal current and resistance?

.009 amps and 1150 ohms

The circuit has a 200 ohm resistor in series with a 500 ohm and a 300 ohm resistor which are in parallel with each other. The voltage supply is 20 volts. What is the total current and resistance for the circuit?

.052 amps and 387.5 ohms

The circuit has a 50 ohm in series with two 100 ohm resistors which are in parallel with each other. The voltage supply is 10 Volts. What is the current and total resistance for the circuit?

.1 amps and 100 ohms

A coil has an inductance of 1.5 H and a wire resistance of 6 ohms. If the coil is connected to a battery of 3 V. how long will it take the current to reach its full Ohms law value

1.25s

There are 3 factors that determine the amount of voltage that will be induced in a conductor.

1.They are the number of turns of wire 2.the strength of the magnetic field 3.the speed of the cutting action

A parallel circuit has three resistors rated at 20 ohms, 40 ohms, and 40 ohms. The total resistance of this circuit is _____ ohms

10

A series circuit has five resistors and the total voltage applied to the circuit is 120 volts. Four of the resistors have voltage drops of 35 volts, 25 volts, 30 volts, and 20 volts. The voltage drop of the fifth resistor is _________ volts.

10

When the color gold is used in the multiplier band, it means to divide the numeric value of the first two bands by ____.

10

When the color silver is used in the multiplier band, it means to divide the numeric value of the resistor by ____.

100

If a parallel circuit contains two resistors whose values are 30 ohms and 20 ohms, the total resistance of the circuit is ____ ohms.

12

A series circuit contains four resistors and the total resistance of the circuit is 420 ohms. Three of the resistors have values of 70 ohms, 80 ohms, and 150 ohms. The value of the fourth resistor is ___________ ohms.

120

In a combination circuit, a 100-ohm resistor is in series with two 50-ohm resistors that are in parallel with each other. The total resistance of the circuit is ________ ohms.

125

The circuit has a 50 volt supply with a 250 ohm resistor which is in series with two parallel 500 ohm resistors which are in series with a 250 ohm resistor. What is the total resistance and current?

750 ohms and 67 milliamps/.067 amps

Using Ohm's law, it would take ________ volts to push 4 amps of current through 20 ohms of resistance.

80

Carbon resistors will change their value because of ____

Age, Over heating

A coil wound on a non magnetic core material such as wood or plastic is referred to as

Air Core Inductor

Which of the following is an example of a good conductor of electricity?

Aluminum

In parallel circuits, the voltage across each branch of the circuit is ____

Always Equal

In a series circuit, the ____ is the same at any point in the circuit

Amperage

The ____ is a measurement of the amount of electricity that is flowing through a circuit.

Amperage

The amount of voltage required to push the electrons through the circuit is determined by the amount of ____.

Amperage and Resistance

The basic building block of the universe is the.

Atom

The force that exists between two objects that contain like electrical charges is called

Attraction

A _________________________ is defined as the amount of heat required to raise the temperature of one pound of water one degree Fahrenheit.

BTU

What direction does Alternating Current flow

Bi directional

A ____ circuit is the conductors that supply power to electrical equipment from the last overcurrent protective device (fuse or circuit breaker).

Branch

___ resistors are made from a compound of carbon graphite and a resin bonding material.

Carbon Resistor

A basic law of physics states that a spinning object will pull away from its center point and that the faster it spins, the greater the ____ force becomes.

Centrifugal

A point used as a common connection point for other parts of a circuit, but is not actually driven into the ground is called a(n) ________ ground.

Chassis

The value of a resistor can often be determined by use of the ____________________.

Color Code

______________ law of electrostatic charges states that the force of electrostatic attraction or repulsion is directly proportional to the product of the two charges and inversely proportional to the square of the distance between them.

Columbs Law

Before current can flow through a circuit, a _________________________ must exist

Complete Path

A ____ is generally made from material that contains one or two valence electrons.

Conductor

According to Ohm's law, an increase of resistance must cause a proportional decrease of ____.

Current

Electrical ____ is the flow of electrons

Current

The total _______ flow in a parallel circuit is equal to the sum of the currents through all of the branches of the circuit.

Current

When using Fleming's generator rule, the center finger shows the direction of the ____

Current induced into the armature

A device used to prevent induced voltage spikes when the current flow through an inductor is stopped is the _______.

Diode

permits current to flow in one direction

Diode

When using Fleming's generator rule, the forefinger points in the direction of the ____

Field flux

Resistors that have a tolerance of plus/minus 1%, as well as some military resistors, contain ____________________ bands of color.

Five

____ resistors have only one ohmic value, which cannot be changed or altered.

Fixed

When using the color code to determine the value of a resistor, the ____________________ band is the tolerance band, when the tolerance of the resistor is 5% or 10%.

Fourth

A circuit where a path other than the one intended is established to ground is said to be ____

Grounded

The ____ conductor provides the return path and completes the circuit back to the power source.

Grounded or Neutral

A conductor connected to the case of an appliance to provide a low-resistance path to ground is called a(n) ____ conductor.

Grounding

Electrical current will flow through the ____ conductor only when a circuit fault develops.

Grounding

The ____ conductor is used to help prevent a shock hazard in the event that the hot conductor comes in contact with the case or frame of an appliance.

Grounding

All electricians should know that whenever current flows through a resistance, ____________________ is produced

Heat

A coil has an inductance of one ____ when a current change of one ampere per second results in an induced voltage of one volt.

Henry

The standard measure of inductance is the

Henry

The standard measure of inductance is the?

Henry

Iron core inductors cannot be used for _______-frequency applications because of eddy current loss and hysteresis loss in the core material.

High

The polarity of the ____ voltage is determined by the polarity of the magnetic field in relation to the direction of movement.

Induced

An exponential curve shows the rate at which current increases or decreases in a(n) ____.

Inductor

The reciprocal of any number is that number divided ___

Into 1

A coil wound on a core of magnetic material such as silicon steel or soft iron is referred to as

Iron Core

While inductance is proportional to the number of turns of wire, the type of core material used, and the cross-sectional area of the core, it is inversely proportional to the core ____

Length

____ law states that an induced voltage or current opposes the motion that causes it

Lenz

The basic laws of physics states

Likes repel Opposite Attract

In an electrical circuit, the ____ offers resistance to the circuit and limits the amount of current that can flow.

Load

____ is the amount of power a circuit is supplying to an electrical device.

Load

One of the basic laws of electricity is that whenever current flows through a conductor, a ______ is created around the conductor

Magnetic field

The most common method of producing electricity is ____.

Magnetism

any substance that has mass and occupies space.

Matter

A device that can be used for voltage spike suppression in either AC or DC circuits is the ________ varistor

Metal oxide

When using the color code to determine resistor values, the third band is called the ____________________ band.

Multiplier

A ____ charge is formed by an excess of electron

Negative

A point in a circuit when current reaches a junction point of resistors and splits is called

Node

Neutrons and proton's of an atom combine to form the

Nucleus

If a circuit contains three resistors whose values are 50 ohms, 30 ohms, and 70 ohms, and the total resistance of the circuit is 150 ohms, the circuit is a

Parallel Circuit

Producing electricity from light involves the use of particles called ____.

Photons

The production of electricity by pressure involves the striking, bending, or twisting of certain crystals that is referred to as the ____ effect.

Piezoelectric

A charge formed by a lack of electrons is said to be

Positive

The most common popular name for variable resistors is ____________________.

Pot

a series circuit, the total power used in a circuit is equal to the sum of the ________ used by all the parts of the circuit.

Power

The 3 principal parts of an atom are

Proton, Neutron and Nucleus

The atomic number of an element is the same as the number of ____ in the nucleus.

Protons

The number of ____ in the nucleus determine what kind of element an atom is.

Protons

In a parallel circuit,the amount of current flowing through each resistor is inversely proportional to its ____.

Resistance

The total amount of resistance to current flow in a series circuit is equal to the sum of the ____ in that circuit.

Resistance

The definition of _____________ is that the total resistance of a circuit can be found by adding the values of all the resistors in that circuit.

Resistance adds

Producing electricity with heat is referred to as the ____ effect

Seebeck

A _______ circuit is a circuit that has only one path for the current to flow.

Series

In a ____ circuit, the current is the same at any point in the circuit

Series

In a ____ circuit, the sum of the voltage drops of the individual resistors must equal the applied voltage.

Series

In a ____ circuit, the total resistance is the sum of the individual resistors

Series

In a _______ circuit, all the lights on a circuit would have to be on in order for any one light to operate.

Series

The total amount of power in a ____ circuit is equal to the sum of the power used by all the parts.

Series, Parallel, Combo

In which of the following types of circuits can the total power of the circuit be determined by adding the power dissipation of all the parts of the circuit?

Series, parallel, Combo

A ____ circuit is a circuit with very little or no resistance

Short

A circuit with little or no resistance in it is called ____

Short Circuit

___ is the best natural conductor of electricity

Silver

A large amount of voltage that exists for a very short period of time is called a voltage _________.

Spike

Metal oxide varistors are often found in ________ used to protect many home appliances such as televisions, stereos, and computers.

Surge Protectors

Resistors also have a power rating in watts that should not be exceeded or the resistor will be damaged.

True

When using the color code to determine resistor values, the first ____________________ bands represent number values.

Two

What direction does Direct Current Flow

Unidirectional

Any electrons located in the outer shell of an atom are known as ____ electrons.

Valence

Lenz's law states that

an induced voltage or current opposes the motion that causes it

In a series circuit, the sum of the voltage drops equals the ____________.

applied voltage

The polarity of the induced voltage is determined

by the polarity of the magnetic field in relation to the direction of movement

The purpose of the magnetic core in a typical transformer is to

concentrate and direct the magnetic field.

When using the product over sum method of determining the total resistance of a parallel circuit, you would ____

divide the total of R(1) times R(2) by the total of R(1) plus R(2)

In parallel circuits, when all resistors are of equal value the total resistance is equal to the value of one individual resistor ____

divided by the number of resistors

Basic electricity is the flow of

electrons

Rubber, wood, plastic, and glass are good examples of ____ materials

insulator

The disadvantage of the metal film resistor is that ____

it costs more than carbon resistors

When working with electrical equipment that requires sensitive adjustments, ____ resistors are usually used.

multiturn variable

The amount of current leaving the source ____

must equal the current returning to the source

A(n) ____ is the amount of resistance that allows one ampere of current to flow when the applied voltage is one volt.

ohm

the total resistance is equal to the ____

reciprocal of the sum of the reciprocals of the branch resistances product of the resistors divided by the sum of the resistors when the circuit has two resistors value of one resistor divided by the number of resistors when the circuit contains two or more resistors of the same value

When dealing with the concept of load, many students incorrectly believe that an increase of _______ results in an increase of load.

resistance

Fleming's left-hand generator rule can be used to determine

the relationship of the motion of the conductor in the magnetic field to the direction of the induced current.

The principle of magnetic induction states that

whenever a conductor cuts through magnetic lines of flux, a voltage is induced into the conductor.

Most AC generators and alternators operate on the principle of the

wire being stationary while a magnet is moved through the coil.


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