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Rules for series circuts

1. sum of all voltage drops is equal to total voltage 2. current is common 3. Sum of all resistances is equal to total resistance 4. Sum of all power is equal to total power

Batteries store

DC power

A capacitor can block

DC voltage

Mutual inductance is measured in

Henrys

You must be aware of which lead is more negative than the other

To read the voltage drop across the resistors

Electrons travel

at the speed of light

An AC generator does not require

burshes and commutators to work

Voltage drop can damage

electric motors

Voltage

electric potential energy per unit charge measured in joules per coulomb

Q and the bandwidth are

inversely proportional

Diode

only lets current flow one way

Period

the time required for one cycle of AC to occur

Germanium diodes have a forward voltage of

.3 volts

Silicon diodes typical rating

.7 volts

With silicon diodes the forward pressure is

.7 volts

What is the equation for RMS Voltage

.707 multiplied by peak voltage

The RMS value

.707 of the peak value

the formula for Capacitve Reactance

1 over 2 pi multiplied by frequency multiplied by capacitance

Semicondcuter material is pure to what specification

1 part in 10 billion and may have impurities added at approximately 1 part per 10 million to increase the number of carriers

Procedure for solving parallel circuits

1. Draw the circuit diagram 2. State the values were given and the values to be found 3. Select the equations to be used in solving for the unknown quantities based upon the known quantities 4. Substitute the known values into the equation you have selected and solve for the unknown value

Three alternative methods to calculate resistance in a parallel circuit

1. Reciprocal of the reciprocal 2. Product over the sum 3. Rt=R (branches) over number of branches

Five rules of magnetic lines of flux

1. They take the most direct path 2. They never cross 3. Travel from north to south 4. Only pass through permeable material 5. Opposites attract, likes repel

What is the equation for peak voltage

1.414 multiplied times RMS voltage

One Watt equals

1/746 horsepower

Effective value of household AC

115 Vac

How far apart are phases in aircraft

120 degrees

Peak voltage for househould AC

165 Vac

Zener voltages range of error

5 to 10 percent

In Europe, the standard power line frequency is

50 Hertz

Coluomb is equal to

6.28 billion-billion electrons

In the USA, the standard power line frequency is

60 hertz

Power points are at

70.7% of peak power

Angle Notation

A vector with magnitude

Transformer process description

AC voltage is inducted in the unpowered secondary coil equal to the AC voltage across the powered primary coil multiplied by the ration of the secondrary coil turns to primary coil turns

Stores energy

An instructor's magnetic field does this

P type material form the

Annode with holes

Wheatstone Bridge construction

Arranged in a square four resistors, two that have a fixed or equal value on top, on the bottom one is equal to the top resistors and one has a variable value. The corners are connected to electrical source with a galvanometer connected across the opposite corners. The variable resistors is connected until the galvanometer reads zero. Thus showing the ratio of the variable resistor and its neighbor is equal to the ratio of the unknown resistor and its neighbor

Inductance is the opposite of

Capacitance

Only stores electrons

Capacitors can't produce electrons, instead they

Dampening wave

Each cycle of a tank circuit a little bit of energy is lost so over time the amplitude of the sine wave will steadily decrease

Good Insulators

Elements that don't give up valance electrons no matter what force is applied

Examples of insulators

Glass, Mica, Silica

Ohm's Law

I= V/R, Current is equal to Voltage divided by resistance

Kirchoffs Current Law is also known as

Kirchoffs first law, Kirchoffs point rule, Kirchoffs junction rule and Kirchoffs first rule

Kirchoffs Voltage Law is also known as

Kirchoffs second law, Kirchoffs Loop Rule, Kirchoffs Second Rule

Electron donors are also known as

N-type dopants

Four factors that control capacity of an inductor

Number of coils, material of the coils wrapped around the core, cross sectional area of the coil, and the length of the coil

Impedance and Inductance reactance caused by inductors in an AC circuit is referred to in

Ohms

Ideal reistors

Ohms law resistors that cannot exist in the real world but are close enough to reality to be useful

Good conductors

Only those elements that dont hang on to their valence electrons

In order to determine the total impedance

Reactance and resistance are required

RCL stands for

Resistor, Capacitor, and Inductor

Pure waves

Square, triangle, or saw tooth voltage/current wave forms that real life often distorts

The reason oscilloscopes are so accurate in capturing the crests of the waveform

The fast action of the cathode ray tube in response to changes in voltage

Choke inductor

Uses an inductor to change the output of the ripple voltage that would begin to flatten the peak voltage

In ELI the iceman, ELI means

Voltage (E) in an Inductive Circuit (L) leads Current (I)

Best known bridge circuit

Wheatstone Bridge

Mutual inductance

When an emf is produced in a coil because of the change in current in a coupled coil

The peak voltages are reached only for an instant

Why would a power calculation based on peak values be incorrect

Impeadance is symbolized by the letter

Z

Circuit impedance is symbolized as

Z with Hpp subscript

Zener diodes are maunfactured with

Zener voltages ranging anywhere from a few volts to hundreds of volts

A rotary inverter is nothing more than

a DC motor driving an AC generator

Symbol for RMS

a V with a RMS subscript

Symbol for peak voltage

a V with a peak subscript

Watt

a basic unit of electrical power that is the product of voltage multiplied by current

Chemical reactions

a batteries method of producing electrons on one terminal and absorbing elections on the other terminal

Peak voltage is not a good measure of

a circuit's voltage since most of the time it is less than that

One watt is produced when

a circut that has one amp of current flowing under a pressure of one volt

Wye connected winding does not contain

a closed loop in which parasitic currents can flow preventing such losses

Having a current waveform 90 degrees out of phase with the voltage waveform creates

a condition where power is alternately absorbed and returned to the circuit by the inductor.

Resonance

a condition where the capacitive and inductive reactance of an LC circuit are equal

Q in a circuit is

a description of the quality of the circuit

A semiconductor is

a device that only conducts electricity part of the time

Inverters

a device that performs the opposite function of converting DC to AC power

A bleeder resistor provides

a discharge path for the capacitor preventing a possible shock after the equipment has been turned off

A bleeder resistor also provides

a fixed load no matter what equipment is connected to the power supply

Magnetism describes

a force that can influence the flow of electons

A birdge circuit is a type of rectifier known as

a full wave rectifier

The circle with the wavy line inside is

a generic symbol for any AC voltage source

A capacitor is like

a little battery

lators

a material or device used to prevent the passage of heat, electricity or sound from one medium to another

Magnetic permeability

a measure of ease that lines of magnetic flux travel through a material

Protons contain

a positive electrical potential

Bandpass is expressed as a

a range of the powerpoints between high and low

When a pure AC waveform is sent to a bridge rectifier circuit the output is

a ripple voltage

In a DC circuit, an inductor is

a simple coil of wire

Zener diode

a special type of diode that can handle breakdown voltages without failing completely

A lamp connected to a 6 volt RMS AC supply will supply the same amount of brightness as

a steady 6 volt DC supply

A square wave could be produced by

a transitor acting as a switch

Thermistors are represented by

a zig zag line with a line moving through diagonally and ending in a flat line

Potentiometers are represented by

a zig zag line with a perpendicular to an arrowed line

Rt=R (branches) over number of branches

accomplished by putting the value of the resistance branched over the numbers of branches

Coluomb is the

actual count of electrons in a unit of measure

Total capacitance reactance in a parallel circuit is found by

adding the inverse sums, product over methor or the value divided by the sum of branches

Protons positive charge

affect the orbits of the electrons

Kirchoffs Current Law

algebraic sum of the current flowing away from any point in an electrical circuit is equal to the sum of the current flowing to that point

You can apply Ohms law only if

all terms are representative of their respective quantities between the same two points in the circuit

Practical average of points means

all values assumed to be positive

Sine-Wave

alternating current waveform that is produced by a rotary generator

Joule

amount of electrons in a suspended state as compared to some electrons in an adjacent part of the circuit

I is the symbol for

amps

A static inverter produces

an AC waveform using solid states devices

The symbol capacitive reactance is

an X with a c subscript

P type seminconductors are doped with a trivalent impurity and have

an abundance of free holes

Impedance

an electrical characteristic of a conductor when an alternating current is applied

Static Electricity

an electrical charge that may be built up on a non-conductive surface by friction

A capacitor

an electrical component used to store electrical energy in the form of an electrostatic field

Rectifier

an electronic devise that convers AC voltage to a type of DC

Schottky Diode

another diode that does operating in both forward bias and breakdown

The familiar battery symbol is a generic symbol for

any DC voltage source

A dielectric can be

any non conductive substance

180 degrees is the most that

any vector can be out of phase

Loads slow current by

applying resistance

Electronic meters specifically designed for RMS measurement

are best for measuring RMS

Phase angle

are differences between two similiary vary quantites (sine waves)

Reistors

are electrical devices that manage the flow of current through a circuit by creating a drop in voltage between two points

Surface mount resistors

are marked numerically and their value is obtained by consulting technical data

Henrys and Farads

are opposite of one another

Both reactance and resistance

are required to determine impedance

The devices in a circuit

are the source for each type of wave

Impedance half power points

are the two points on the impedance curve that are 70.7% of the peak impedance value

Parallel circuits

are those that offer several paths for current flow

A half wave rectifier can be something

as simple as a single diode placed on an AM radio signal

Average value of a waveform

average the values of all the points on a waveform's graph to a single aggregate number mathematically

Four methods of resistor identification

axial color code, part number, base color code, direct measure

Q is a ratio of the

bandwidth to the peak current curve

Coulomb

basic unit of electrical quantiy

Volt

basic unit of measure of electrical pressure

Power factor interest engineers

because it represents the efficiency of the system

Analog meter movements will work for RMS measurements so long as they have

been calibrated for RMS figures

When forward biased, a Zener diode

behave much the same as standard rectifying diodes. They have a forward voltage drop that follows the diode equation and is about to .7 volts

Materials used in a capacitor

best suit the capacitors function

Wire wound resistors are typically ranged

between 5 and 200 watts

A diode is added to AM systems to

block out all the negative values

A capacitor's electrical property

blocks DC voltages and passes AC voltages

Capacitance Reactance is symbolized

by a capital X with a C subscript

Capacitive reactance is symbolized

by an X with a c subscript

Inductive reactance is symbolized

by and X with an L subscript

You can determine the frequency in Hertz

by measuring the period on the wave on the horizontal axis of the oscilloscope screen and reciprocating that time value in seconds

Air

can be a good insulator but will spark when enough electrical force is applied

Secondary batteries

can be recharged because the application of a voltage can release the electrons back into solution

Bridge rectifier

can be recognized by the square arrangement of the diodes in a sort of diamond with current given two paths to flow depending on the polarity of the input signal

Half-power points, bandwidth, bandpass, and circuit quality

can only exist in a circuit operating at one resonance frequency

Maximum impedance

cancels out the signal entirely

Reactance arises from

capacitance and inductance within a circuit

If X < 0 it is

capacitive

Filter circuits used in power supplies are of two general types

capacitor input and choke input

A sawtooth wave could be produced by

capacitors or inductors

If the frequency increases then

capacitve reactance will decrease

Reactance is present in addition to resistance when conductors

carry alternating current

N type material from the

cathode with free electons

Flashover

caused by brief spikes of voltage irrespective of time

Nucleaus

center of the atom

The inductor opposes

changes in current to provide smoother output for the load

A high frequency alternating current

changes more rapidly than a low frequency one

Pi filter

combination of the simple capacitor input filter and the choke input filter

In a parallel circuit, voltage is

common through each of the branches

Bridge Circuit

contains four impedances or resistances that form a square

The value of an AC voltage is

continually change from zero up to the positive peak, through the negative peak and back to zero again

Reactive power is the sum of

current and voltage used by the inductive and capacitive reactance in a circuit

A Magnetic Field is built when

current first starts flowing through a coil

ICE stands for

current leads voltage

Inductance causes

current to lag voltage in phase

Capitance causes

current to lead voltage in phase

Faraday's Law

current will flow in a circuit provided there is electrical difference in potential and there is a path for it to flow

First rule of resistance

current will take the path of less resistance

As reverse bias increases, capacitance

decreases, the maximum voltage that a varactor diode can withstand is determined by its maximum capacitance level

First use of the diode

demodulation of amplitude modulated radio broadcast

Full wave center tapped rectifier

depending on where the load is tapped, the output is a ripple dc voltage which allows for an inversion of the signal

Symbols orientation is important to

determine the flow of current

What determines whether the vector is positive or negative is

determined if the circuit is more capacitate reactant or inductive reactant

the closest element electrically to the rectifier

determines the basic type of filter being used

Nitrogen and phosphorus are N type dopans for

diamond

Dielectric

dictates what type of capacitor it is and what it is best suited for

IFSM

diode, maximum (peak or surge) forward current

VR or VDC

diode, maximum DC reverse voltage

IF(AV)

diode, maximum average forward current

VF

diode, maximum forward voltage

VRRM

diode, maximum repetitive reverse voltage

PD

diode, maximum total dissipation

TJ

diode, operating junction temperature

TSTG

diode, storage temperature range

rectifying property

directionality of current flow most diodes exhibit

Power factor is the ratio of

dissipated power over input

To determine the total inductive reactance in a parallel circuit

divide one by the sum of the individual inductive reactances after dividing one by them

In the reverse bias mode, Zener diodes

do not conduct until the applied voltage reaches or exceeds the zener voltage at which point the diode can conduct substantial current and in doing so twill try to limit the voltage dropped across it to that Zener voltage point

Resistors are used for

drop voltage in a circuit and control voltage to obtain a particular outcome

In series parallel cicuits,

each section needs to be worked to its simplest elements then reworked to fill in the unknowns

Conductors

easily permit the movement of electrons from an electrical source to a load and back to the electrical source with a minimum of resistance

When the current is flowing in the forward bias direction then the

effective resistance is near zero

The RMS value is the

effective value of a varying voltage or current

Unless otherwise specified all values of AC voltage are considered

effective values

Reactance produces a phase shift between

electric current and voltage in the circuit

With AC it is possible to build

electric generators, motors, and power distribution systems that are far more efficient than DC

Resistance is

electrical opposition to the current flow in a conductor

Direct Current

electricity flowing in a constant direction, possessing a voltage with constant polarity

Transformer operation depends on

electromagnetic induction between two stationary coils and a magnetic flux of changing magnitude and polarity

In a diode

electron current only flows in one direction

simple triangle with a straight line

electronic symbol for a diode

Henries = (4 x PI x #turns x #turns x Coil Area x MU)/ (coil length x 10,000,000)

equation for calculating the number of heneries in an inductor is

Current is divided in a parallel circuit

evenly between the branches

Mica, ceramic, cellulose, porcelain, Mylar, Teflon, Air

examples of dielectrics used in capacitors

Applying a voltage to the N type material does what

excites the free electrons that quickly fill the holes in the P type material

Step up transformers

fewer turns in the primary winding than in the secondary winding the secondary voltage will be higher than the secondary circuit

Step down transformers

fewer turns in the secondary winding than in the primary winding, the secondary voltage will be lower than the primary

During conductance an extra valence electron

flows into the next atoms valance orbit

Rugged diodes are especially useful

for HF radio waves

Typical aircraft generators only have

four wires on the output of the busses

N type donor impurity creates

free electrons

The reactance is proportional to the

frequency

Current flows

from a negative electrical potential to a positive one

Sine waves rise and fall

from peak back to zero

Most semiconductors are constructed of either

germanium or silicon or some similar crystalline type material

The reactance of a capacitor

goes down as the frequency increases

Semiconductor materials are produced by

growing them in round tubes that are etched and doped with impurities to give them their semiconducting properties

Types of rectifiers

half wave and full wave

Thermistor

has a lower resistance at higher temps

LDR or Light Dependent Resistors

have lower resistance where there is more light

General purpose oscilloscope

have the ability to display voltage from virtually any voltage source plotted as a graph with time as the independent variable

Delta connected windings can allow

high frequency parasitic electrical currents to circulate entirely within the motor

AC is used predominately for

high power applications

Wye configuration gives

high torque at low rpm, but not as high top rpm

The attraction of opposite charges

holds the electron in its orbit

P type acceptor impurity creates a

hole, a positive charge carrier

Each component produces

impedance in the circuit that is a resistance to current flow

Exactly 180 degrees out of phase

impedance is very high

Resistance is measured

in Ohms and uses the omega symbol

Voltage is common

in a parallel circuit

DC equivalent and equivalent are sometimes used

in place of RMS

Radio waves are generated

in radio frequency ranges RF

The choke input filter uses an inductor

in series with the load resistor

Neutrons are not involved

in the conduction of electricity

Bridge Circuit is a type of electrical circuit

in which the current in a conductor split into two parallel paths and then recombines into a single conductor thereby enclosing a loop.

The width of a varactor diodes depletion region

increases and decreases via changing the level of the diodes reverse bias

If the frequency increases, the inductive reactance

increases proportionally

Capacitance is the opposite of

inductance

If X > 0 the reactance is

inductive

Circuit quality equation

inductive reactance divided by resistance

The significance of power factor lies

int he fact that utility companies supply customers with a volt amperes but bill them for watts

Third color band

is a power of ten multiplier or the number of zeros that must be added to the first two numbers

Fourth color band

is a resistors tolerance

Inductive reactance

is associated with the vary magnetic field that surrounds a wire or a coil carrying a current

Total capacitance reactance in a series circuit

is determined by adding the values of the of the individual capacitve reactances together

The sum of all the voltages around the loop

is equal to the applied voltage

The instantaneous voltage across a wire coil

is equal to the number of turns of that coil around the core, multiplied by the instantaneous rate of change in magnetic flux linking with the coil

The voltage of a capacitor in a parallel RCL circuit

is equal to the voltage at the inductor

A bleeder resistor

is found in practically all power supplies

Fundamental significance of a transformer

is its ability to step the voltage up or down from the powered coil to the unpowered coil

Electron's charge

is negative

The difference in produced polarity from the 90 degree position from the 270 degree position

is opposite

Magnetism

is the ability of a magnet to attract certain materials containing iron and other ferrous material

Effective Voltage

is the amount of AC that produces the same amount of heat as a corresponding value of DC

One Henry

is the amount of inductance a current change of one amp per second induces a voltage of one volt

The only resistance to current flow across a diode

is the amount of voltage it takes to push the diode into forward bias

When dealing with measurements of electric power, RMS amplitude measurement

is the best way to relate AC quantities to DC quantities

Capacitive Reactance

is the capacitiors opposition to change in the AC voltage

Root Mean Square

is the effective value of sine wave alternatin current

EMF

is the force required to cause one amp of the current of flow through one ohm of reistance

Electromotive Force

is the force required to move an electron measured in volts

Reactance

is the imaginary part of electrical impedance, a measure of opposition to a sinusodial alternating current

Capacitance Reactance

is the opposition to current flow in a circuit that is produced by a capacitor

Voltage Drop

is the reduction in voltage in an electrical circuit between the source and load

Rules for calculating resistors in an AC circuit

is the same as DC

In a parallel circuit the total current load

is the sum of the currents in the banches

In phase impedance

is very low

Counter or Back EMF

is voltage applied to a conductor that opposes the applied EMF

When transmitting electrical power over long distances

it is far more effecient to do so with stepped up voltages and stepped down currents and then step the voltage back down and the current backup for the industry business or consumer use

When an AC motor produces a pure sine wave

it will need to be conditioned to be useful in DC circuits

capacitor input filter will

keep the output voltage at a higher level compared to a choke input

The speed of rotation combined with electrical potential

keeps the electrons in their orbits

Varactor Diode

known as varicap diodes are a simple electronic component

One ohm

limits the flow of current to one amp under a voltage pressure of one volt

Motor with windings in a delta configuration gives

low torque at low rpm, but can give high top rpm

A battery is a device

made of one or more individual electrochemical cells used to store chemical energy and make that every available in chemical form

When an AC voltage is applied to the primary coil it creates a

magnetic flux in the core, which induces AC voltage in the secondary coil in phase wit the source voltage

Around magnets are

magnetic flux lines that travel from the north end of the magnetic to the south

First two inner orbits

make up the atomic number for the element

Complex Impedance

may be used interchangeably with impedance because impedance is a complex quantity

A bridge circuit was originally used for

measurement purposes

Capacitors are typically measured in

micro farads

Wye winding is normally

more effecient

Four band identification

most common used color coding scheme on all resistors

in electronics, varactor diodes are

mostly utilized as voltage controlled capacitors

P type material has only holes and cannot

move free electrons

Reverse breakdown voltage and breakdown voltage is typically

much much greater than forward voltage

Product over sum

multiply the individual resistances then divide that product by the sum of the resistances

Kirchoffs voltage law describes how the algebraic sum of all voltages in a loop

must equal zero

Current flows from

negative to positive

Neutrons are

neutral subatomic particles

N type dopants includes elements such as

nitrogen, phosphorus, arsenic, and antimony

180 degree position

no lines of flux are being cut by the conductor and the voltage and current are at zero

Static electricity serves

no useful purpose in aviation and cost millions of dollars in damage every year

400 Hertz

normal AC frequency for aircraft use

AC from generators used for power are

normally at realatively low frequencies

Pure silicon or germanium by themselves are

not particularly good conductors and in their pure state are insulators

Capacitance is the ratio

of charge impressed on a given conductor

Cathode bar

of the diode symbol corresponds to N type semiconductor

Air dielectric

often used in radio turning circuits

Magnetic permeability is based

on the ratio of magnetic flux density in a substance to the magnetizing force that produces it

Primary batteries

once expended cannot be recharged

Tank circuits have how many frequencies that they will oscillate at

one

At resonance, a tank circuit will operate as

one component

Physically a tank circuit is

one inductor and one capacitor wired in parallel

Resistance does what

opposed or slows down another force, drops, voltage and consumes power

No other current will flow as long as a circuit is

oscillating

Reactance

part of electrical impedance, a measure of opposition to a sinusoidal alternating current

When rating insulators for service in high voltage AC applications

peak voltage measurements are the most appropriate because the principal concern here is insulator flash over

An oscilloscope is the best way to

perform peak and peak to peak measurements

Reactive Power

phantom power that is a result of the voltage and current used by the instructors and capacitors in an AC circuit.

Frequency is equivalent to

pitch

Intrinsic semiconductor materials are

poor conductors

90 degree

position at which the most positive current and voltage are produced

Protons

positively charged subatomic particles

Ripple is the amplitude excursions from

positve to zero and black, of a waveform from the pure DC value the alternating component of the rectifier voltave

Supercapacitors

power electric and hybrid cars

Apparent Power

product of effective voltage and effective current that is expressed in volt amps rather than watts without reference to phase shift if any, between voltage and current

Polyphase

production of two or more phases of AC or of two or more alternating voltages of the same frequency

Atoms are made up of

protons, neutrons and electrons

if X = 0 then the circuit is

purely resistive

Diode current rises

quite rapidly for modest increases in voltage drop

Power factor

ratio of the actual power dissipated in an electrical system to the input power of volts multiplied by amps

X symbolizes

reactance

The resistance that is produced by the capacitors and the inductor are called

reactance which is impedance to current flow

The diode does what to AM signals

rectifies them, leaving a signal whose average amplitude is the desired audio signal

Atoms

represent the smallest elements that exist in nature

Magnitude

represents the ratio of voltage difference amplitude to the current amplitude

A Volt is that amount of force

required to cause on amp of current to flow through one ohm of resistance

Capacitance reactance is measured as

resistance to current flow

Impedance is the sum of resistance to current flow in

resistance, capacitance, and inductance

A bridge circuit essentially

reverses one cycle of the incoming AC signal

Two types of inverters

rotary and static

Phosphorus, arsenic, and antimony are used with

silicon

.7 and 1.4 are useful for

sine waves

Simple resistors are represented by

single zig zag line

Impedance only refers to the resistance of

sinusoidal alternating current

AC voltage changes

sinusoidally from zero to peak rather than linearly

The actual diode in a circuit may be a

small clear crystal device or a small cylindrical device with a band on one end to indicate the cathode

purpose of the power supply filters is to

smooth out the ripple contained in the pulses of DC obtained from the rectifier circuit while increasing the average output voltage or current

Depending on size and type dielectric

some capacitors are better for high frequency uses, while others are better for high voltage

Provides an excellent analogy for relating AC concepts

sound waves, especially music

Problems involved with using brushes

sparking, heat, and wasted energy

ECG

special purpose oscilloscope expressly designed for medical use

As a varactor diode's voltage increases

specific energy supplies must be provided for the circuits driving the diode

Wye wound is sometimes called

star windings

AC voltage value

starts at zero, increases to its maximum positive value, then returns to zero

Batteries and capacitors both

store electrons

Zig zag line

symbol of a resistor in an electrical schematic

A full wave rectifier

takes the negative AC cycle and reverses its polarity to put it in between the positive AC pulses

The heart of an oscillator

tank circuit

Zener voltage changes slightly with

temperature

Tank cirucits store energy

temporarily

The current through a forward biased PN junction is proportional

th the raised power of the forward voltage drop

The anode arrow corresponds to

the P type semiconductor

Effective voltage of AC is

the RMS value

True power

the actual power available in an AC circuit

Doping

the addition of the desired impurity to a semiconductor

Kirchoffs Voltage Law

the algebraic sum of all the voltave drops in any closed circuit is equal to zero

A farad measures

the amount of Colombes that can be applied or stored on one side of the capacitor

Ohms law states

the amount of current flowing in a circuit is directly proportional to the circuit voltage and inversely proportional to the circuit resistance

Standard P N Diodes are rated by

the amount of current required to forward bias

A magnetic field is directly proportional to

the amount of current that flows through the conductor

Dividing the load resistance into the applied DC voltage squared

the amount of power being delivered to a DC circuit load

Phase angle refers to

the angular component of the polar coordinate representation in the context of vectors and phasors

Any capacitor or conductor's capacitance depends on varying factors such as

the area of conductive plates the dielectric constant of the insulator between the plates and the distance between the two plates

Sound is generated in an AM system by

the average value is extracted using a simple filter and fed into an audio transducer

Henry

the basic unit of measurement for induction

RCL circuits are

the basis for the operation of tank circuits inside oscillators

If the capacitance increases then

the capacitive reactance will decrease

Frequency is determined by

the capacitor and inductor of the circuit

True power is the product of

the circuit voltage and the current in phase with this voltage

DC generator construction

the coil of wire is mounted on the shaft where the magnet is on the AC alternator. Electrical connections are made to this spinning coil via stationary carbon brushes containing copper strips on the rotating shaft. This allows for constant polarity but the amplitude will vary as the rotor rotates

Purely restive circuits

the complexities of AC are of no practical consequence

Doping increases

the conductivity of a semiconductor so that it is more comparable to a metal than an insulator

At the 90 degree position

the conductor is moving the fastest and the most line of flux would be cut

270 degree position

the current and voltage is at maximum again though the conductor is moving across the lines of flux in the opposite direction

According to Kirchoffs Current Law

the current entering any junction is equal to the current leaving that junction

Ripple is defiened as

the departure of the waveform of a rectifier from pure DC

Unidirectional device

the diode

Capacitance Reactance describes

the effect that capacitance has on an AC circuit

The more rapidly the applied voltage changes in value

the faster the capacitor stores energy

First two bands encode

the first two significant digits of resistance value

Reactance is also the measure of the opposition to

the flow of alternating current caused by the inductance and capacitance in a circuit rather than by resistance

Current is

the flow of electricity that pass a given point in a specific amount of time

Inductors resist

the flow of electrons

Direct current is defined as

the flow of electrons in one direction throughout a circuit with constant voltage and current

Alternating current is

the flow of electrons that continuously changes its value in magnitude and periodically reversed direction (sine-wave)

Flywheel effect

the flowing of current between a capacitor and inductor in a tank circuit

Bandwidth is

the frequency difference between the upper and lower half power points

In fuel tank quantity gauges, the dielectric is

the fuel in the tank

The higher the frequency and the larger the inductance

the harder it is for current to flow through the inductance, it meets more opposition

If we listened to an un-rectified signal

the highs and lows of the AC signal would cancel each other out and we would only hear the static hiss

A parallel circuit is at resonance with

the impedance is at maximum and the current is at a minimum

Since the capacitor and inductor are matched value wise in a parallel RCL circuit

the impedance would be the same

Mutual inductance

the induction of a voltage in one coil in response to a change in current in the other coil

If the inductance increased then

the inductive reactance increases proportionally

Regenerative feedback

the injection of the right amount of energy into the circuit to maintain the amplitude

Unlike normal inductance, mutual inductance is symbolized by

the letter M rather than the letter L

When AC voltage is applied to a conductor

the magnetic field will expand and contract at the same rate as the applied frequency

When DC voltage is applied to a conductor

the magnetic field will remain stationary

Control of exactly when current is allowed to flow

the major difference between free electrons in a transistor and current

Peak or Crest value of an AC waveform

the measure of AC quantity from its peak heigh on a waveform graph

The more rapidly the current changes

the more an inductor resists it

By using two diodes that share a common tap at the middle of the transformer

the negative pulse is effectively inversed at the output

`Frequency

the number of cycles of AC completed in one second.

Inductive Reactance

the opposition to current flow in a circut that contains an inductor

Reactive power is also used to describe

the out of phase power associated with inductors and capacitors

The three phase describes

the output of three stator windings

RMS current measurement is the best to use because

the principal concern with current is overheating of the wire which is a function of power dissipation caused by current through the resistance of the wire

Resonance frequency is equal to

the product of one half pi the square root of the value of the inductor times the capacitor

Apparent power is

the product of the readings of an AC voltmeter and an AC ammeter

Positive and negative cycles of an AC signal cannot be heard when broadcasted together because

the rate of change of the carrier is so fast

Amplitude modulated signal has a voltage that cycles at

the rate of the carrier

Resonance operation refers to

the relationship between the total current of a circuit as compared to the total impedance

In ELI the ICE man, ICE is

the relationship of Current (I) as being in front of of leading Voltage (E) for the capacitor (C)

The diode will only allow current to flow in one direction as long as

the reverse bias voltage of the diode is not exceeded

Simple circuits involving nothing more than AC power source and resistance

the same laws and rules of DC apply simply and directly

You solve for inductive reactance in a parallel circuit

the same way you would solve for parallel resistors in a DC circuit

Inductive Reactance is proportional to

the signal frequency and the inductance

At any point in an electrical circuit that does not represent a capacitor plate

the sum of currents flowing towards that point is equal to the sum of currents flowing away from that point

To determine the total inductive reactance in a series circuit

the sum of the individual inductive reactance equals the total

Z

the symbol for Impedance

Delta configuration connects

the three winding to each other in a triangle like circuit and power is applied at each of the connections

The rate of alternation

the time it takes for a wave to evolve before it repeats itself expressed as cycles per unit time or frequency

If asked to determine impedance in a parallel cuircuit, you will need to determine

the total current in the circuit

A parallel RCL circuit is operating in resonance when

the total impedance is maximum and the total current is at a minimum

Impeadance is

the total opposition of a circuit to alternating current

Kirchoff's laws about power loss in a series circut

the total voltage drop of all resistors is equal to the total applied voltage

What makes a semiconductor possible

the type of materials and how those materials are constructed

Farad

the unit measure for a Capacitor

Hertz

the unit of measure for Frequency. One Hertz is equal to one cylce of AC per second

Bandwidth is established between

the upper half power point and the lower half power point

Henrys only describe

the value of the inductor and not the impedance the device contributes to the circuit

Second rule of series circuits

the voltage drop at each resistor will be the sum of total applied voltage

If source voltage is given in AC RMS volts

then all calculated currents and voltages are cast in AC RMS units as well

If source voltage is given in peak AC volts

then all currents and voltages are subsequently calculated regarding peak units

If a vector value is 0

then the vector is considered to be in phase

For a DC generator to produce constant voltage

there are multiple sets of coils making intermittent contact with the brushes

When the magnetic field is increasing around the winding of the inductor

there is an impedance to current because of current being used to increase the magnetic field

Once current is flowing in a diode

there is no more resistance caused by the diode

First rule of series circuits

there is only one path for current to flow therefore current equal throughout the circuit

Breakdown

this is a voltage in the negative charge that if exceeded you can damage the diode

Fixed resistors are

those whose value cannot be changed

Mechanical, Chemical, Friction

three methods used to generate EMF

Wye Wound usually describes

threes phase AC generator used on modern jet aircraft

Wye wound connects all the windings

to a central point and power is applied to the remaining end of each winding

Capacitive reactance is inversely proportional

to both frequency and capacitance

Impedance is the total opposition

to current flow of AC in an electrical circut

Usual purpose of the transformer is

to transform one voltage to another

RCL computations are used

to understand how AC voltage reacts to the various types of components

Transformer

transforms electrical energy into magnetic energy then back into electrical energy again

Rectifying diode is a simple symbol is

triangle shape against a flat line

Photo resistors are represented by

two angled and arrowed lines pointing toward a zig zag

Steel and Iron

two examples of magnetically permeable metals

Inside a capacitor

two metal plates separated by a dielectric

A capacitor is made of

two parallel conductors seperated by an insulator called the diaelectric

Symbol for capacitor

two parallel lines

the formula for inductive reactance

two pi multiplied by frquency multiplied by inductance

Out of step

two waveforms are not synchronized

Amps

unit of measure used to express the flow of electrons

Ceramic dielectric

used for high frequency purposes like antennas, Xrays, and MRIs

Mylar dielectric

used for timer circuits

Glass dielectric

used in high voltage applications

Two diode rectifier

used in power conversion

Oscilloscope

used to display changing voltage over time on a graphical screen

Peak to Peak (P-P)

value of an AC waveform measured from the total height of opposite peaks

Ohms law works becasue

values of voltage, amps, and ohms are mathematically even

Varactor diodes have

variable capacitance which is a function of the voltage impressed on its terminals

Five main types of resitors

variable, potentiometers, thermistors, photo resistors, and simple

Charge time in a simple capacitor and Pi L filter is

very fast compared to discharge time

Sine waves are values of

voltage and current that start at zeror and smoothly rise to a peak value

Adding more diodes in series would add to the

voltage drop across all of the diodes

ELI stans for

voltage leads current

A diode effects voltages in parallel circuits

voltage taken off a branch will only equal the voltage that is allowed to pass the diode

If you apply an electrical voltage to the P type material

voltage will not be able to flow

Transformers can change a higher

voltage with less current or lower voltage with higher amps

Rotary electro-mechanical generators naturally produce

voltages alternating in polarity, reversing positive and negative over time

E is the symbol for

volts

NASA uses glass capacitors for

waking up the shuttle's circuitry

Nonsinusodial wave

waveshape that does not bear a close resemblance to a perfect sine wave

If larger regulated voltages are required

we could either use more diodes in series

If we plot the average of the ripple voltage

we measure much less than the peak voltage

The direction of current being produced in the conductor can be determined by knowing what two things

what direction are the lines of flux and what direction the conductor is cutting those magnetic lines of flux

Oscillator

what produces the carrier wave in most radios

Junction

when P and N materials are bonded together

Reverse bias

when P type material has voltage applied and no voltage can flow

Forward Bias

when a diode begins to conduct current

Magnetic Field

when current flows in a conductor, a magnetic field is formed

Forward bias

when current is flowing through a transistor

Reactance can also occurs for short intervals

when direct current is changing as it approaches or departs from the steady flow

When a diode is considered a variable resistance device

when the forward bias is low then the resistance of the diode is high

In a bridge rectifier only two diodes

will be forward biased at any given time

A capacitor hooked to a battery

will charge and discharge giving the appearance of DC voltage

Total voltage used by all the resistors

will equal the total voltage applied

Circuits with a high Q

will have a narrow bandwidth

Circuits with a low Q

will have a wide bandwidth

Excessive voltage drop

will result in unsatisfactory operation of electrical equipment and energy wasted in the wiring system

Wye Wound

windings arranged in the shape of a Y

Delta wound

windings that are arranged in the shape of a triangle

If a resistor greater than 2 watts rating are needed

wire wound resistors are used

Phase angle is synonymous

with phase

The Pi filter is a capacitor input filter

with the addition of an L section filter

Concerning sine waves, the top or zero

would be where the conductor is cutting through no lines of flux

The average voltage of an AC signal is

zero because the positive and negative cancel each other out

Variable resistors are represented by

zig zag line with a diagonal angle


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