Electronics Information pt 1

Electric charge

a property where electrically charged objects are accelerated by electrical forces

Electricity

the flow of electrons along a conductor

Conductor

an object that allows electrons to pass easily

Elements

most basic materials in the universe

Free electrons

electrons that move from atom to atom at random

A conductor is any material that ___

has many free electrons

Speed of light

186,282 miles per second

Current flow

when a flow of electrons along a conductor occurs

Magnetism

a force that acts between certain objects

Magnetic field

the area around a magnet where the force is felt

Electromagnet

a coil of current carrying wire

Conventional Current flow

positive to negative charges

Electron Current

negative to positive charges

Direct Current (DC)

flows continuously in the same direction

Alternating Current (AC)

flow periodically reverses direction

Circuit

A pathway for the movement of electrons

Electromotive Force

external force on electrons to make them flow through a conductor

Volts

electric pressure

Measurement of Ampere

6.25 quintillion electrons in 1 second

Ampere

electrical current

Coulomb

6.25 quintillion electrons stores on an object

Current Formula

current = charge in coulombs / time in seconds

Milliampere (mA)

1 thousandth of an ampere

Microampere (µA)

1 millionth of an ampere

Ammeter

measures current flow in a circuit

Milliammeter

measures smaller current flow in a circuit

Microammeter

measures very small current flow in a circuit

Voltmeter

measures voltage

Multimeter / volt-ohm-milliameter

measures both voltage and current plus resistance

Silver as a conductor

is better than copper but more expensive

Copper as a conductor

is used more since it is cheaper

Aluminum as a conductor

is used where light weight is important

Electric current

when electrons are made to move in the same direction

Good insulators

plastic, rubber, or cloth material

Smaller gauge wire equals

larger diameter

Semiconductor

materials that have conductive properties between conductors and resistors

Common semiconductor materials

silicon and germanium

Intrinsic

pure

Resistors

opposite of good conductors

Ohms

resistance to electron flow

Power

the rate at which work is done

Watts

power

Joules

energy work

Watt formula

watt = joule per second

Horsepower

moving a certain weight a certain distance in 1 minute

How much watts equals 1 horse power

764 watts of electric power to equal 1 horse power

Power formula

power = volts X amperes

Kilowatt

used to express the amount of electric energy used or available

Kilowatt amount is

1 thousand watts

Milliwatt amount is

1 thousandth of a watt

Larger the wire

the smaller resistance per foot of length

Thermistors

decrease in resistance with an increase in temperature

Resistors provide

measured amount of resistance

Resistance symbol

Wirebound resistors

are made of wire that has controlled resistance per unit length

Carbon-composition resistors

are marked according to their ohmic value

Mega

Million

Conductance

the ability of a material to pass electrons

Siemen

unit of conductance

Ohms Law

E = I X R (Voltage = Current X Resistance)

Complete Current is made of

a source of electricity, a conductor, and a consuming device

Open Circuit

no current flows

Batteries negative charge

excess of electrons

Batteries positive charge

deficiency of electrons

Closed/Complete Circuit

a single path for electrons to flow

Series Circuit

two or more resistors or consuming devices are placed on after another

Kirchoffs voltage law

the sum of all voltages across resistors or loads is equal to the applies voltage

switch symbol

ground symbol

Fuse

used to prevent the damage done by excess current flowing in a circuit

fuse symbol

Inductance

the ability of a coil, choke, or inductor to oppose any change in circuit current

Transformer

changes electricity into a higher or lower voltage

Alternator

coverts mechanical energy into AC electrical energy

Waveform

Pattern

Sine wave

the basic waveform of AC or voltage

One hertz

equal to one cycle per second

Capacitor

device that opposes any change in circuit voltage

Capitance

the property of opposing voltage change

Rectifiers

changing AC to DC

Diode

a device that allows current to flow in one direction

Transistor

used to amplify or switch a signal

Battery

a device in which chemical energy is converted to electrical energy

What makes up a battery

two electrodes and an electrolyte

Electric motor

changes electrical energy into mechanical energy

Voltmeter

checks voltage

Ammeter

checks current

Wattmeter

checks performance of power

Ohmmeter

checks resistance

Transducer

devices that convert pressure, light, heat, and sound to electrical energy

Solder

an alloy metal made from tin and lead

Soldering

the technique of joining electrical connections where solder is melted to form a joint

Flux

a chemical that cleans the area of connection

Contact soldering

uses a soldering iron or soldering pencil