Flashcards in 12 Electricity Deck (39)

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1

## Current

###
Electron flow (I)

How much charge (how many electrons) pass through certain point in circuit per unit time

Quantity measured in Amperes

Body current = ion movement

2

## Capacitance

###
Stored charge

Substance ability to store a charge

3

## Inductance

### How electricity generated

4

## Ohm's Law

###
I = V / R

Analogous to Q = ΔP/R or BP = CO x SVR

5

## Voltage

###
Electromotive force (EMF) or force that pushes electrons through resistance

Electrical charge potential difference directly proportional to electron flow (electric current)

Driving pressure P1 - P2

Measured in Volts

6

## Resistance

###
Opposition force to electron flow

Flow inversely proportional to resistance

Measured in Ohms

7

## Coulomb

###
Electric charge measure unit

1e¯ = 1.602 x 10^-19

1 Coulomb = 6.24 x 10^18 electrons

1 Coulomb e¯/sec = 1 Amp

8

## Ampere

###
Ampere (Amp) measures current

1 Amp = charge movement carried by 6.24 x 10^18 electrons passing a certain point in 1 second

1 Amp = 1 Coulomb electric charge movement

9

## I = V / R

###
Current = voltage/resistance

E = I x R

Electromotive force (E) = voltage

E = I x Z

Impedance (Z)

10

## Impedance

###
Represented by Z

Resistance to current flow that changes w/ frequency

Power supply frequency at constant 60Hz

Impedance & resistance are interchangeable

High impedance = low current flow

Low impedance = high current flow

11

## Watt

###
Power unit (work/time)

Joules/second

Electrical power measurement

W = V x I

12

## Joule

###
Watt-second = work = energy

Work = mass x acceleration x distance

kg x m/s^2 x m or 1 Joule

13

## Work

###
Force x distance (displacement)

Force = mass x acceleration

Measured in Joules

14

## Energy

###
Kinetic = (mass x velocity^2) / 2

Potential = mass x 9.81m/s^2 x height

15

## Power

###
Measured as Watts in electrical circuit

I x V

16

## Conductor

###
Permits e¯ flow

Current = e¯ flow through conductor

17

## Non-Conductors

###
Insulators

Tightly bound electrons that do not permit e¯ flow

Ex: glass, rubber, plastic, dry wood, pure water

18

## DC

###
Direct current

e¯ flow always in the same direction

Ex: batteries

19

## AC

###
Alternating current

e¯ flow reverses direction (oscillates) at regular intervals

Oscillating frequency measured in cycles per second (Hertz or Hz)

Ex: electric company

20

## Capacitance

### Substance ability to store a charge

21

## Capacitor

###
Electrical device used to shore electric charge

Basic design - 2 parallel conducting plates separated by insulating layer called dielectric

22

## Electromagnetic Field

###
Force field that consists both electric & magnetic components

Resulting from electric charge motion & containing definite amount electromagnetic energy

Electrons flow through wire induce a magnetic field around

When wire coiled repeatedly around an iron core → amplifies the magnetic field

Dual nature r/t electricity & magnetism

- Where there's an electric current there are also magnetic waves

- Where there are changing magnetic waves there's an electric current

Able to do work

23

## Inductance

###
e¯ flow via wire induce magnetic field surrounding

When wire coiled repeatedly around an iron core this will increase the electromagnetic field to move e¯

Ex: wireless charging

24

## Motor

###
Battery source

Metal bar w/ coiled wire

Fixed magnets

Opposing magnetic fields repel e¯ to rotate the metal bar

25

## Generator

###
No power source

Fixed metal bar w/ coiled wire

EMF moves around wire → inductance

Magnets rotate to power light bulb

26

## "Hot" Conductor

### Carries the current through the impedance

27

## "Neutral" Conductor

### Return the current to the source

28

## Shock Hazards

###
Contact external electricity source

AC or DC current

Source - when person becomes part or completes an electric circuit; must contact the electric circuit at 2 points and there must be voltage source causing current to flow

29

## Electricity Damage

###
Current disrupts normal cell electrical function

Or current passing through resistance (body) increases the temperature and can produce a burn

Severity depends on amount of current (Amperes) & contact duration

30