Basic Electricity Ch 3 Section A Vocabulary

Ion

A charged atom. Ions are created because of unbalanced electrostatic conditions which cause the atom to be charged.

Fuse

A device which is used to protect a circuit when excessive current flow occurs.

Electrostatic field

A field of force that exists around a charged body also referred to as a dielectric field.

Insulator

A material that does not allow electrons to move through it easily. Its atomic structure is between five and eight valence electrons.

Conductor

A material that has an atomic structure which allows for electrons to flow through them easily, materials with less than 5 electrons are good conductors. Examples, silver, gold ,copper, aluminum.

Resistivity

A material's opposition to the flow of electric current. opposite of conductivity

Solenoid

A remotely activated electrical device. A coil of wire with a movable core is activated by completing an electrical circuit

Static wick

A series of devices located on aircrafts control surfaces which concentrate the electricity on one point and then discharges the energy into the air

electromagnetic induction

A transfer of electrical energy from one conductor to another by means of a moving electromagnetic field.

Volt

A unit of electrical pressure or electromotive force that is needed to move one ampere of electrical flow through a resistance of one ohm.

Ohm

A unit of electrical resistance in a circuit

Rheostat

A variable resistor having only two terminals. it is normally used in a circuit to drop voltage by dissipating some of the energy as heat

Potentiometer

An instrument used for measuring the differences in electrical potential by balancing the unknown voltage with a known voltage.

Static Electricity

Electricity that is stationary in nature ; a buildup of excess electrical charge on a material

Ohms Law

Is a basic statement which states that the current that flows in circuit is directly proportional to the voltage (force) that causes it and inversely proportional to the resistance (opposition) in the circuit.

Coulomb (Q)

It is a basic unit of measurement which account for electrical quantity and is comprised of 6.28 billion billion electrons. It is symbolized as Q.

Electron flow

It is the flow of electrons from the negative through the load and into the positive terminal.

Electron

Negatively charged particles which surround the nucleus and fly around the it at a speed of 186,282 miles per hour and have very little mass.

Piezoelectric Effect

Occurs when a crystalline material such as quarts is subjected to mechanical pressure which causes an excess of electrons to accumulate on one surface.

Retentivity

The ability of a material to stay magnetized (inversely proportional to permeability)

Watt

The basic unit of electrical power. One ampere flowing under a pressure of one volt is equal to one watt. One watt equals 1/746 Horse Power (HP)

Magnetomotive Force

The magnetizing force in a magnetic field that is measure in gilberts or ampere-turns

Reluctance

The opposition to the establishment of a magnetic field in a material. opposite of permeability.

Current (I)

The rate of flow of electric charge. Is also symbolized as I

Photoemissive

The tendency of a material to emit electrons when exposed to light.

Conventional flow

The theory that suggest that electricity flows from a positive to a negative terminal which had been discovered to be incorrect.

Maxwell

The unit of magnetic flux in the gaussian-cgs system.

Ampere/Amp

This is when one coulomb of electrons is able to flow past a certain point in one second. One ampere is the amount of current that can be forced through one ohm of resistance by a pressure of one volt.

Resistor

Used in electrical circuits to control the amount of current flow. converts some electrical energy into heat.

Thermocouple

a loop made of two different metal wires joined at both ends, where a voltage is generated when a temperature difference exists between the two junctions, causing a small electrical current to flow through the loop

Permeability

a material's ability to allow magnetic field lines to pass through it

lodestone

a piece of magnetite or other naturally magnetized mineral, able to be used as a magnet.

Circuit breaker

a switch that opens when the current in a circuit is too high. once the circuit cools down it can be reset

Circular Mil (CM)

area of a circle having a diameter (d) of one mil. ​

Power (P)

power is the product of voltage (e) times current (I)

Relay

simply an electrical switch that is operated from a remote location with contacts that are closed or opened by an electromagnetic field

Electromotive force

the driving force that pushes electrons through a circuit, essentially the "electrical pressure" responsible for the movement of electrons, and is measured in volts.

Gauss

the total electric flux through a closed surface is directly proportional to the total electric charge enclosed within that surface; essentially, it means the number of electric field lines passing through a closed surface is related to the charge inside that surface

Square mil

unit of cross section of small diameter conductor whose side is equal to one mil.

Gilbert

unit of magnetomotive force equal to 0.7968

Left hand rule

wrap the four fingers of your left hand around the coil so that the fingers point in the direction in which the electrons are flowing from the negative terminal of the dry cell to the positive