Principles Of Electricty

Question 1

Electricity def

Answer 1

Form of energy that products light, heat, and magnetic and chemical changes

Question 2

Electrons def

Answer 2

A flow of tiny, negatively charged particles

Question 3

Electric current def

Answer 3

Flow of electrons that move along a path called a conductor

Question 4

Conductors def

Answer 4

Material that best transports electricity
Best are silver and copper; others include metals, graphite, carbon, and water-containing ions

Question 5

Insulators def with examples

Answer 5

Material that doesn’t allow current to pass through; conductor is contained in an insulator

Silk, plastic, rubber, wood, glass, paper, air, brick, cloth, liquid paraffin, and pure distilled water

Question 6

AMP/ampere def

Answer 6

A unit of electric strength; the amp rating indicates the number of electrons flowing on a line

Question 7

1 ampere = _______ milliamperes

Answer 7

1000

Question 8

Volt/voltage def

Answer 8

A unit of electric pressure; measures how hard the electrons are being forced or pushed by the source

Question 9

OHM def

Answer 9

A unit of electric resistance; every conductor has a specific rate at which it will allow electrons to move through it; tells how difficult to push electrons though

Question 10

The amount of resistance in a conductor is determined by

Answer 10

Size, material, and temperature

Question 11

Watt def

Answer 11

A measure of how much electrical energy or power is being used per second

Question 12

1 watt is a ___ amount of energy

Answer 12

Small

Question 13

1 kilowatt =______ watts

Answer 13

1000

Question 14

Source of how electric current is produced

Answer 14

Provides the force to move electrons in the conducting material

Question 15

2 common sources of electric current

Answer 15

Battery
Generator

Question 16

Battery description

Answer 16

Has a positive and a negative terminal; produces only direct current

Question 17

Generator description

Answer 17

Most often used in a salon/spa; produces alternating current; uses mechanical energy to produce a flow of electrons

Question 18

Two conditions that must exist for electric current to be produced

Answer 18

A source and a circuit

Question 19

Circuit def

Answer 19

Closed path through which the electrons travel

Question 20

Two types of circuits

Answer 20

Closed and open

Question 21

Closed circuit def

Answer 21

Path of electron flow from source to operate appliance

Question 22

Open circuit def

Answer 22

Path through which the electrons travel is broken

Question 23

Two ways circuits can be connected to power loads

Answer 23

Parallel wiring
Series wiring

Question 24

Parallel wiring def

Answer 24

More than one item can be plugged into the same circuit; each item can be run alone or at the same time

Question 25

Series wiring def

Answer 25

All loads run at the same time; circuit travels from one load to the next

Question 26

2 forms of electric current

Answer 26

Direct current (DC) Alternating current (AC)

Question 27

Direct current description

Answer 27

Electrons move at an even rate only in one direction (ex: battery) Used in electrotherapy devices (galvanic)

Question 28

Alternating current description

Answer 28

Most common current used in businesses and homes; electrons flow first in one direction and then in the other Used in a high frequency device (tesla)

Question 29

The nameplate of an appliance tells you

Answer 29

Frequency (Hz) needed Volts needed (120v or 240v) Watts appliance consumes per second (100w, 200w, etc)

Question 30

What does an inverter do and an example

Answer 30

Changes direct current to alternating current Mobile charger in car

Question 31

What does a rectifier do and what is an example

Answer 31

Changes alternating current to direct current Block between your wall plug in and device

Question 32

What does a rheostat do and an example

Answer 32

Adjusts flow of current that can change volume or intensity of voltage Dims lights; controls speed of motors

Question 33

What does a transformer do and an example

Answer 33

Transfers electricity by an oscillating magnetic field that connects two or more electrical circuits Reduces high voltage electricity to lower voltage

Question 34

What does a capacitor do and an example

Answer 34

Stores an electrical charge Unlike a battery, it releases energy quickly; does not produce new electrons Lasers

Question 35

Polarity refers to

Answer 35

The negative and positive poles at the ends of a circuit

Question 36

Changes in polarity create

Answer 36

Waveforms

Question 37

Waveform def

Answer 37

Visual representation of the output current that varies in time, strength, and direction

Question 38

Waveform pulse is a combination of

Answer 38

Phases that make up a single portion of the waveform

Question 39

Rectangular waveform description

Answer 39

Pulse wave Has constant amplitude over the pulse duration

Question 40

Square waveform description

Answer 40

Periodic waveform that instantly transitions between 2 levels of rise and fall times at a steady frequency

Question 41

Sinusoidal waveform description

Answer 41

Smooth wave Linear wave motion with periodic rise and fall times in a motion that is up-and-down or side-to-side

Question 42

Saw-toothed waveform description

Answer 42

Periodic linear fave form in which the rise time and fall times at are different

Question 43

Triangular waveform description

Answer 43

Periodic linear waveform that has rise and fall times that are equal

Question 44

Overload circuit def

Answer 44

More current flows than the line is designed to carry Fires can occur when an extension cord is used to attach four or five appliances to one wall outlet

Question 45

Short circuit def

Answer 45

Can occur anytime a foreign conductor comes in contact with a wire carrying current to an appliance Dropping an appliance into water will cause the current to flow though the water causing a short circuit

Question 46

Safety measures of fuses

Answer 46

Cannot be reused Contains a fine metal wire; allows current to flow through it If overload occurs, fuse heats up and wire melts, breaking the circuit and cutting flow of electricity

Question 47

2-prong grounding description

Answer 47

Polarized outlets feature 2 slots of different sizes Slot for neutral wire is wider making it difficult to insert plug the wrong way

Question 48

3-prong grounding description

Answer 48

In addition to vertical slots, round hole for the grounding conductor

Question 49

Static electricity def

Answer 49

A stationary electric charge, typically produced by friction that causes sparks or crackling or the attraction of dust or hair; can be extremely dangerous

Question 50

Fire extinguisher PASS

Answer 50

Pull pin Aim hose Squeeze handle Spray chemical