DC

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Good insulation materials such as glass and mica, have relative resistance at least _____ time that of copper

1,000,000

most digital multimeters have an input opposition to current flow of _____ M(Ohm's) for all voltage ranges except the 200 MV range, which has an opposition to current flow of 40 M(Ohms)

10

The third shell of an atom can hold ___ electrons

18

Resistors with no tolerance band have a tolerance of _____

20

Potentiometers have _____ terminals

3

The ______ is called permeability

Ability of a magnet to carry magnetic lines of force

A _____ is an electromechanical device that indicates readings by the mechanical motion a pointer

Analog Multimeter

A _____ resistor is made by applying a film of carbon to a ceramic rod

Carbon Film

_____ is a mixture of fine particles of glass or ceramic and powdered metals such as silver, platinum, or gold

Cermet

_____ force is the force needed to remove a materials residual magnetism

Coercive

____ electrification occurs when a conductor connects two objects with different charges

Conduction

A switch uses ___ electrification

Contact

A _____ is an instrument that indicates an open or closed circuit in a circuit in which all power is OFF

Continuity Checker

In an _____ circuit, there is very little resistance and a dangerously large amount of current flows

Short

In the SI system, conductance is measured in _____

Siemens

1000,000,000 lines of force per meter squared is called _____

Tesla

Name does not determine the amount of induced voltage in a coil

The direction of current flow

The greater the distance away from a magnet _____ the magnetic field

The weaker

The _____ of a resistor indicates the plus and minus limits of a resistor's ohmic value

Tolerance

What does the fourth band of color on a 4 band resistor indicate

Tolerance

A _____ coils are used for current tranformers

Toroids

____ contacts are used in high current applications because of thier melting temperature

Tungsten

A resistor whos vales can be varied over a range of values is called a _____ resistor

Variable

A _____ is the unit of 100 million magnetic lines of force cut in one second

Volt

It takes one ______ to push one ampere of current through one omh of resistance

Volt

In general, ______ use a higher voltage source and more powerful battery source than that used by ordinary multimeters

Voltmeters

Increasing the speed at which a conductor cuts the magnetic field increases the _____

Volts

A ____ is equal to one joule per second in the metric system

Watt

_____ is the ability of a device or circuit to generate reactance to oppose a changing current

Electromagnetic induction

_____ is the field produced by the current through a conductor

Electromagnetism

Voltage is also known as _____

Electromotive force

_____ current flow will be used in this class

Electron

It is believed that magnetism can be explained by _____ spin patterns that spin in the _____ direction

Electron, Same

A ______ is a substance that cannot be chemically broken down and contains atoms of only one variety

Element

The _____ is the time curve for current in a inductive resistive circuit

Exponential curve

Iron, soft steel, nickel, cobalt manganese are classified as in rare earth materials

Ferromagnetic

_____ is a material that can be easily magnetized

Ferromagnetic

_____ fuses are cartridge fuses with round ends

Ferrule

Resistors that only have one ohmic value are called _____ resistors

Fixed

One magnetic line of force per square inch is called _____

Flux density

The coefficient of a coupling is the percentage of a magnetic lines of _____ created by one coil that cut the windings of the second coil

Force

One line of force per centimeter sqaured is called _____

Gauss

A _____ consists of a block of metal that transfers the head from the resistor to the chassis

Heat Sink

The unit of measurement for inductance is the _____

Henry

A coil has an inductance of 1 _____ when a current change of one _____ per second results in an induced voltage of one volt

Henry, Ampere

Which one is not a disadvantage of rare earth magents?

High retentivity

What is the main advantage of rare earth magnets

High tesla rating

A semiconductor is a material that exhibits an electrical conductivity between that if a conductor _____ and that of an insulator _____

High, Low

Wire wound resistors are often used because they are able to operate at _____ power levels than other resistors

Higher

The strength of a coils magnetic field is affected by all of the following factors except _____

Hysteresis loss

With an electromagnet, when the number of coil turns in increased, there level of induced voltage is _____

Increased

Rowlands law involves all of the following variable except

Inductance

_____ is the opposition a circuit has to change in current due to energy stored in a magnetic field

Inductance

Abrupt removal of a power from a circuit often causes coils to fail because of _____ kick

Inductive

A _____ is a passive device that stores energy in the form of a magnetic field

Inductor

A _____ opposes a change of current

Inductor

The high voltage that is produce when the magnetic field collapse in an inductive coil is called _____?

Kick back spikes

The _____ rule for conductors can be used to determine the direction of magnetic lines of force around the conductor

Left-hand

_____ law states that voltage and current induced in an inductor oppose the force that produces it

Lenz's

A solenoid is a = electric output device that converts electrical energy into _____ mechanical force

Linear

What were early natural magnets known as

Lodestones and Leading Stones

A _____ should never be used om=n energized circuits

Ohmmeters

The greek symbol Omega represents _____

Ohms

_____ is a material that can not be easily magnetized

Parramagnetic

In a ______, energy is required to create a magnetic field, but no energyy is required to maintain a magnetic field

Permanent magnet

_____ is the measurement of the property of a core material that allows the passage of magnmetic lines of force

Permeance

A _____ temperature coefficient is an increase in the resistance of a material with an increase in temperature

Positive

A _____ are normally used as voltage dividers

Potentiometer

A variable resistor is also called a _____

Potentiometer

A variable resistor with three terminals is called a ______

Potentiometer

Resistors are normally described by electrical resistance, tolerance, _____, method of construction, and circuit application

Power Rating

The physical size of a resistor can give you the _____ of a resistor

Power Rating

The efficiency of a system is the ratio of the _____ output to the ______ input

Power, Power

_____ motion is the speed at which a conductor cuts a magnetic field

Relative

The resistance to magnetism is called _____?

Reluctance

The south pole of one magnet is broguht close to the south pole if another magnet, will the magnets repel or attract each other

Repel

_____ is the opposition to the flow of electrons

Resistance

_____ is the resistance of a material of a specific cubic size

Resistivity

Permaennt magnets have a high _____?

Retentivity

_____ is a material ability to retain magnetism

Retentivity

If the range of voltages is required, a _____ can be used in place of a resistor to provide as adjustable output voltage

Rheostat

_____ induction is the property of a conductor to induce voltage within itself due to changes

Self

Germanium and Silicon are used to make _____

Semiconductors

The conductor with the lowest resistivity is _____

Silver

Ampacity is the maximum amount of current a conductor can carry continuously without exceeding its _____ rating

Temperature

The four factors affecting the resistance of a substance are type of material, conductor length, conductor cross section area and __________

Temperature

The force of electrostatic attraction or repulsion is directly proportional to the product of the two charges and inversely proportional to the sqaure of the distance between them. This is _____ law

Coulombs Law

Heat is produced and electrical energy is consumed when _____ meets resistance

Current

The induce voltage (CEMF) is proportional to the rate of change of _____

Current

What electronic component is often used in a AC circuit to prevent large voltage spiked from being produced when the current flow through an inductor is suddenly terminated

MOV

A _____ circuit is the path taken by the magnetic lines of force

Magnetic

_____ is the current through a coil multiplied by the number of turns on the coil

Magnetomotive force

One magnetic line of force is called flux or _____

Maxwell

Megohmmeters are often referred to as Meggers _____, high voltage and insulation resistance testers

Meggers

A ______ resistor is made by applying a film of metal to a ceramic rod in a vacuum

Metal Film

A _____ resistor is made by combining metal with glass and then applying it to a ceramic base as a thick film

Metal Glaze

When applicable, the fourth band in a five band resistor represents ____

Multiplier

_____ inductance is the effect of one coil inducing a voltage into another coil

Mutual

A _____ coil is an inductor that has coils wound in such a manner that the inductance created by one coil is canceled be an adjacent coil turn

Noninductive

the power formula and _____ law can be combined to find any unknown value if two of the values are known

Ohm's

magnetic lines of force traveling in the same direction _____ each other

add to

____ meters are test instruments used to measure direct current and must have a very low resistance that does not substantially change the value of the current in the circuit

ampere

Magnetic lines of force traveling in the opposite directions _____ each other

cancel

A(n) _____ is an example of an overcurrent protection device

circuit breaker

A(n) _____ is an overcurrent protection device with a fusible link that melts and opens a circuit when an overload condition or short occurs

circuit breaker

A simple electrical circuit must have a(n) _____, a voltage source, and a load

conductor

A(n) _____ is a control device that uses a small input current to energize or de-energize the load connected to it.

contactor, control-relay, and motor starter

all switches use _____ to start or stop the flow of electrons in a circuit

contacts

In Ohm's law, the voltage of a circuit divided by the resistance is equal to the _____

current

clamp-on ammeters measure the _____ in a circuit

current

the power formula, Watt's law, is the relationship between power, voltage, and _____ in an electrical circuit

current

Lenz's law is the basic principle used to determine the _____ of an induced voltage or current

direction

to show that conductors are connected, a _____ may be places at their intersection

dot

_____ current is unwanted current caused by the rate of change in the induced magnetic field

eddy

A _____ switch is a double-pole, double throw (DPDT) switch that changes the electrical connections inside the switch from straight to diagonal

four-way

The _____ rating is the maximum amount of current that a fuse can safely interrupt without rupturing or arcing over

interrupting

A(n) _____ is a device that converts electrical energy to motion, light, heart, or sound

load

meter _____ is inaccurate readings due to the meters resistance being in parallel with the component under test

loading

an electric _____ is a rotating device that converts electrical power into a rotating mechanical force

motor

electrical measurements are most commonly taken using a(n) _____

multimeter

A(n) _____ occurs when circuit current rises above the level at which the load and or circuit is designed to operate, according to the wording per NEC

overload

_____ devices are required in motor circuits by the NEC

overload

A(n) _____ is an overload device used with motor starter that responds to electrical loads and operates at a preset value

overload relay

an Edison base _____ fuse has a screw-in base similar to a light bulb

plug

A _____ is the number of completely isolated circuits that a relay can switch

pole

A _____ is the part of a switch that determines the number of circuits the switch can control

pole

_____ is the rate of doing work or using energy

power

the _____ in a circuit increases based on a factor equal to the circuit voltage squared divided by the resistance or by the circuit current squared times the resistance

power

_____ is the amount of magnetizing force remaining after the magnetizing force is removed

residual magnetism

In Ohm's law, the voltage of a circuit divided by the current is equal to the _____

resistance

Ohm's law is the relationship between voltage, current, and _____ in an electrical circuit

resistance

A variable resistor with two terminals is called a _____

rheostat

A _____ switch is a switch that has one or more poles that can be connected to several positions

rotary

When possible, conductors being tested with a clamp on ammeter should be _____ surrounding conductors

separated from

in order to measure current flow through a component, a meter must be connected in ____ with the component

series

A _____ switch is a single-pole, double-throw (SPDT) switch

three-way

In Ohm's law, the current of a circuit multiplied by the voltage is equal to the _____

voltage

power cannot be consumed in a circuit unless there is _____

voltage

Multimeters that are set to measure _____ present high opposition to current flow

voltages

In Ohm's law, the current of a circuit multiplied by the voltage is equal to the _____

watts

The resistivity of copper is _____ cmil/ft

10.4

The valence shell or outer shell of an atom can hold a maximum of ___ electrons

8

Whish one of these magnet characteristics is not desirable in an electromagnet

Ability to retain magnetism

Some of the best permanent magnets are made from _____

All of the above

Temperature coefficient is represented in the mathematical equations by the Greek letter ______

Alpha

One _____ is one coulomb of electrons passing a given point in one second

Ampere

A ______ DMM is a DMM that automatically adjusts to a higher range if its initial range is not high enough

Autoranging

The voltage that is produced, when the electrons flow through a coil that is opposite, and opposes the source voltage is called _____?

CEMF

Relative resistance is the comparison of the resistance of a given material to the resistance of ____

Copper

Resistance of a conductor with a negative temperature coefficient _____ with an increase in temperature

Decreases

_____ is a material that can not be magnetized

Diamagnetic

The law of ____ states that opposite charges attract and like charges repel

Electric charges

It takes 5 _____ for current to reach its maximum value in a LR circuit

Time constants

One volt and one amp will produce one _____

Watt

the power formula is often referred to as ____ law

Watt's

100,000,000 lines of force is called _____

Weber

A _____ resistor is made by winding a piece of resistive wire wound around a ceramic core

Wire Wound

A _____ is a place on a switch contact that opens or closes a circuit

break

A(n) _____ circuit has no electron flow

open

Electromagnets are coils that have a core made of electrical steel or _____ material

soft steel

any switch with a ____ that holds its contacts in either the closed or open position has a normal position

spring

A _____ is a mechanical, electronic, or solid-state electrical device that is used to start, stop, or redirect the flow of electrons in an electrical circuit

switch

_____ relays operate by opening a bimetallic strip upon a rise in temperature

thermal overload

_____ and 4-way switches do not ahve ON and OFF marking on them

three-way

A _____ is the number of closed contact positions per pole of a switch

throw


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