MindTap AC/DC

recording meters

___ are used to detect spike voltages, or currents of short duration, or sudden drops in voltage, current, or power

lightning

___ is a natural display of static electric discharge

lodestone

____ is the name for a naturally occurring magnetic material previously known as magnetite

voltage

_____ is defined as the potential difference btw two points of a conducting wire carrying a constant current of one amp when the power is dissipated btw these points is one watt

electron flow

_____ theory states that current flows from the most negative point in the circuit to the most positive point

conventional current flow

_____ theory states that current flows from the most positive point to the most negative point

derated

if a raceway contains no more than 3 conductors, the ampacity of the conductors must be ____

node

in a combination circuit, the junction point @ which a current splits is ofter referred to as a ___

true

in a combination circuit, to identify series and parallel elements, you should trace the currents path(s)

resistance

in a parallel circuit, the amount of current that flows through each resistor is inversely proportional to the ___ value

resistance

in a parallel circuit, the total ___ is less than that of the lowest value resistor

currents

in a parallel circuit, the total current flow is = to the sum of the ____ through all the branches

False

in a parallel circuit, the voltage across each branch must be greater than the previous

applied voltage

in a series circuit, the _____ is equal to the sum of the voltage drops across all the resistors

current carrying

in the NEC, ampacities refer to the _____ abilities of conductors

true

insulators are the only materials that can hold electrons stationary

increase

materials that _____ their resistance with an increase in temperature have a positive coefficient of temperature

false

most devices such as light receptacles in homes are connected in series

false

nuisance static charges are more likely to occur when the air is wet

arrestors

power lines are often protected by lightning _____ that exhibit a very high resistance at the normal volt of the line

friction

producing electricity by ______ is an example of static charge

photons

producing electricity from light involves the use of particles called

false

resistance is measured with a voltmeter

false

resistors with several non-adjustable ohmic values are called fixed resistors

variable

rheostat is a common name for a ____ resistor

false

selenium is an insulator

molecule

smallest part of a compound

false

solving combination circuits includes a step in which you expand the circuit

false

static electricity is caused by a balance of electrical charges

conductors

the NEC310 contains tables dealing with ____ for general wiring

grounding

the ___ conductor is used to help prevent a shocking hazard in the event that the hot conductor comes in contact with the case or frame of the appliance

fourth

the ____ band of color on a resistor indicates tolerance

north

the ____ magnetic pole of a compass needle is attracted to the south magnetic pole of the earth

bump

the ____ theory states that current flow is produced when an electron from one atom knocks electrons of another atom out of orbit

wire-wound

the advantage of a _____ resistor is a higher power rating

true

the ambient air temp considered in relation to a conductor ampacity is the temperature of the surrounding air

resistance

the amount of voltage across a resistor is proportional to its _____

true

the ampere is equal to one coulomb per second

false

the atomic number of an element is the same as the number of electrons in the nucleus

materials

the charge accumulates on an object is determined by the ___ used to produce the charge

true

the cross-sectional area of round wire is measure in circular mils

true

the current divider formula can be used to calculate current flow through any branch of a circuit

False

the current, voltage, power, and resistance in a series circuit can be found by using Coulomb's law

analog

the d'Arsonval movement is one of the most common _____ meter movements

static electricity

the discharge of ____ in thunderclouds creates lightning bolts

true

the general divider formula can be used to determine voltage drop across series elements

false

the longer the conductor, the less the resistance it will have

magnetized

the measure of a material's ability to be _____ is called permeability

false

the measure of a material's resistance to magnetism is known as reluctance

true

the meter that measures true power in a circuit is the wattmeter

true

the most common method of producing electricity is magnetism

false

the nonconductive covering around a wire is the conductor

false

the ohmmeter must be connected to a circuit when the circuit power is turned on

pressure

the production of electricity by ______ involves the striking, bending, or twisting of certain crystals

true

the smallest part of an element is an atom

false

the static charge that accumulates on clothes in a dryer is a useful charge

false

the strength of an electromagnet is primarily proportional to its diameter

current flow

the total _____ in a parallel circuit is equal to the sum of the currents through all of the circuit branches

current flow

the total amount of resistance to _____ in a series circuit is equal to the sum of the resistance in that circuit

true

the unit of resistance to current flow is the ohm

True

the values of a variable resistor can be changed or varied over a range

true

the voltage drop across any branch of a parallel circuit is the same as applied voltage

electrical schematics use symbols to represent the ______ of a resistor

use

true

valence electrons are located in the outer shell of an atom

true

voltage drop can be calculated using Ohm's law

direction

voltage polarity can be determined by observing the _____ of the circuit flow through the circuit

false

wattage is also referred to as emf

shunt

what type of ohmmeter is used to measure low values of resistance

false

when conductors are used in a location with a higher ambient temp, the amp of the conductor must be reduced

1

when determining the total resistance in a parallel circuit, the reciprocal of any number is that number divided by ___

false

when the current in a combination circuit reaches a node, the current is blocked

parallel block

Rc(2&3) refers to the _____ containing R2 and R3

combination

a ___ circuit contains both series and parallel elements

voltmeter

a ____ can be connected directly across the power source because it has a very high resistance connected in series with the meter movement

potentiometer

a ____ is a variable resistor used to provide a variable voltage

btu

a ____ is defined as the amount of heat required to raise the temp of one pound of water one degree fahrenheit

false

a basic law of magnetism states that unlike poles repel and like poles attract

true

a chassis ground is a point that is used as a common connection for other parts of a circuit

false

a chassis ground symbol symbolizes a ground point

false

a complete circuit is often referred to as an open circuit

current

a fuse is designed to open and disconnect a circuit in the event of excessive _____

false

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

true

a method for finding total resistance of parallel resistors is calculating product over sum

true

a multirange ammeter operates on more than one range by connecting the meter movement to different shunts

true

a neutral conductor is also referred to as a ground conductor

False

a series circuit has more than one path to current flow

one

a series circuit is a circuit that has ___ path for current flow

True

a short circuit occurs when there is very little resistance and a large amount of current flow

false

a voltage multiplier is used to provide different voltages btw certain points in a circuit

162

a wire that has a diameter of ____ mils has an area of 26,244 circular mils

True

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

0.1

an ammeter has a typical impedance of less than ____ ohm(s)

false

an ammeter shunt is a high-resistance device

electroscope

an early electric instrument that can be used to determine the polarity of the electrostatic charge of an object is the ____

load

an increase of current, not resistance, results in an increase of _____

magnetism

can be explained in the terms of electron spin patterns

electrons

can form spin patterns that cancel the magnetic field of the material

true

diamagnetic materials are either metal or nonmetal materials that cannot be magnetized

false

direct current is described as bidirectional

true

ferromagnetic materials are metals that are easily magnetized