Flashcards in Electricity -Terms and definitions Deck (97):

1

## I=V/R

###
I = current (A)

(V) = voltage (v)

R = resistance

Ohm's law!

2

## Voltage and Wattage

### If an electrical appliance says "220v, 45w" on it, this means that when it's connected to a voltage of 220v, the power is 45w.

3

## Ohm's Law

### The current in a circuit on an electrical component, depends on the voltage and resistance.

4

## Voltage in a series circuit

### In a series circuit, voltage SPLITS

5

## Power

###
Symbol: P

Unit: Watt (w) or J.s^-1

Power measures how fast energy is transformed (work done).

6

## Centripetal Force & Magnetic Field

###
Fc = F

Fc = (mv^2)/r

F = Bqv

thus

(mv^2)/r = Bqv

7

## Electrical Field Strength

###
Symbol: E

Unit: NxC-1

8

## Electrical Charge

###
Symbol: q

Unit: Coulomb (c)

9

## Resistance

###
Symbol: R

Unit: Ohm Ω

Resistance is the ability of an electrical component to OPPOSE THE FLOW OF AN ELECTRICAL CURRENT

10

## F=BIL

###
F = force (N)

B = Magnetic Field Strength (T)

I = Current (A)

L = effectuve (perpendicular) distance of wire cutting the magnetic field.

11

## Conventional Current

###
Always goes from positive to negative.

In reality, it is actually negative electrons going from negative to positive.

12

## Resistors in series

### Rtotal = R1 + R2 + R3...

13

## P = *E/t

###
P = power (w)

*E = Change in energy (J)

t = time (s)

14

## V = BLv

###
V = Voltage (v)

B = Mgnetic Field Strength (T)

L = Length (m)

v = Velocity (m/s)

15

## dot -Magnetic field

### Going out of the page

16

## Force on Moving Charge in Magnetic Field

###
A charged particle moving inside a magnetic field will experience a force. Use right-hand slap rule.

Force will cause the particle to turn (centripetal force).

Force and Velocity are always at 90°.

NOTE: If charge is negative, thumb should point in opposite direction due to conventional current.

17

## Lenz Law

### The direction of this current/voltage will be such that it will create a force to work against the movement.

18

## Parallel circuit

### When there is more than 1 pathway for electricity to go through

19

## F = Bqv

###
F = Force (N)

B = Magnetic Field Strength (T)

q = charge (c)

v = velocity (m/s)

20

## v=*E/q (*=change in)

###
v = Voltage

*E = Energy (gained or lost) (J)

q = charge (c)

21

## Current in a Parallel Circuit

### In a parallel circuit, the current SPLITS

22

## Charge

###
symbol: q

units: coulomb (c)

def

23

## F=E.q

###
F = force (N)

E = Electrical Field Strength (N.C^-1)

q = charge (c)

24

## Current in a series circuit

### In a series circuit, current STAYS THE SAME

25

## B = (KI)/d

###
B = Magnetic field strength (T)

I = current (A)

d = distance to current (m)

k = constant number: 2.0x10^-2T.M.A

26

## Voltage

###
symbol: V

Is also called the 'potential difference'.

It is the amount of electrical potential energy one coulomb of charge gains or losses across an electrical current.

27

## Magnetic Field

###
Has two poles (North and South). Magnetic field lines travel from NORTH to SOUTH

The lines do not cross eachother

Magnetic field strength is represented by the lines.

Small gaps (tight spacing)= strong magnetic field

Large gaps (lose spacing)= weak magnetic field

Symbol: B

Unit: T (Tesla)

28

## Ammeter

###
Symbol: A

An ammeter has zero resistance

Because of this, the ammeter goes within the circuit, not attached in parallel.

29

## Electromagnet

### A solenoid (densely wounded coil of wire) that creates a magnetic field when current is added. Sometimes an iron core is added to strengthen the magnetic field.

30

## Series Circuit

### When there is only one pathway for electricity to go through

31

## P = VI

###
P = Power (w)

V = voltage (v)

I = current (A)

32

## Current

###
Symbol: I

Is how many coulombs of charge pass through a point in 1 second.

33

## Voltmeter

###
Symbol: v

A voltmeter has infinite resistance

Because of this, the voltmeter must go parallel to the circuit, not within it.

34

## Positive Charge

### In direction of force

35

## Negative Charge

### Opposite direction of force

36

## Resistors in parallel

### 1/Rtotal = 1/R1 + 1/R2 + 1/R3 ...

37

## Faraday's Law

### When a wire is moving through a magnetic field, a voltage/current will be induced

38

## X -Magnetic field

### Going into the page

39

## Right-hand slap rule

###
Thumb: Direction of current

Four Fingers: Direction of magnetic field

Palm (slap): Direction of the force

40

## Ep=Eqd

###
Ep = Electrical potential energy (J)

E = Electrical field strength (N.C^-1)

q = charge (c)

d = distance (m)

41

## P=VI

###
P = power (w)

V = Voltage (v)

I = Current (A)

42

## E=V/D

###
E = Electrical Field Strength (N.C^-1)

V = voltage (v)

d = distance between two plates (m)

43

## Voltage in a parallel circuit

### In a parallel circuit, the voltage STAYS THE SAME

44

## Power

###
Power measures how fast energy is transformed (work done).

Symbol: P

Unit: Watt (W) or J/s

-The brightness of a lamp is dependant on its power. Bigger power = brighter lamp.

-The heat of a heater dependant on power.

Bigger power = heat up faster.

45

## Right-hand Grab Rule

###
(To find the direction of the magnetic field around a wire/coil)

1. Thumb = direction of current

2. 4 fingers = curl in the direction of the magnetic field lines

3. GRAB

46

## P=ΔE/t

###
P = Power (W)

ΔE = Change in energy (J)

t = time (s)

1W = 1 J/s

47

## Faraday's Law

### When a wire is moving through a magnetic field, a voltage/current will be induced.

48

## Lenz Law

49

## V=BLv

###
V = Voltage (v)

B = Magnetic Field Strength (T)

L = Length (cm)

v = velocity (m/s)

50

## Attraction of Electric Charges

### Unlike charges give negative potential energy (attractive force). uUnlike charges attract one another.

51

## Charging by Conduction

### Charging an object by allowing it to come into contact with an object that already has an electrical charge.

52

## Charging by Friction

### Two objects rub together and one becomes positivley charged and the other becomes negativley charged

53

## Charging by Induction

### Charging and object without direct contact (proximity to nearby object charges neutral object)

54

## Conductors

### Materials that allow electric charges to flow through them easily

55

## Coulomb

### Unit used to measure quantity of electric charge

56

## Current

### A flow of electric through a conductor

57

## Current Electricity

### The continuous flow of electrons through a conductor

58

## Direct current

### An electrical current that always moves in one direction

59

## Electric circuit

### Consists of a voltage source and a continuous conducting path for a current to follow

60

## Electric current

### The flow of electric charge electric field force field produced by an electrical charge

61

## Electrical Field

### The field around charged particles that exerts a force on other charged particles

62

## Electrical Field lines

### A map of an electric field representing the direction of the force that a positive charge would experience

63

## Electric flux

### The product of a surface area and the component of the electric field perpendicular to the surface

64

## Electric generator

### A mechanical device that uses wire loops rotating in a magnetic field to generate electricity

65

## Electric Potential

### The difference in electrical charge between two points in a circuit expressed in volts (aka potential difference)

66

## Electrical potential energy

### Potential energy due to the position of charge near or other charges

67

## Electrical conductors

### Materials that have electrons that are free to move throughout the material; for example, metals

68

## Electrical energy

### A form of energy from electromagnetic interactions

69

## Electrical Force

### A fundamental force that results from the interaction of electrical charge

70

## Electrical insulators

### Electrical nonconductors, or materials that obstruct the flow of electric current

71

## Electrical resistance

### The property of opposing or reducing electric current

72

## Electrolyte

### Water solution of ionic substances that conducts an electric current

73

## Electromagnet

### A magnet formed by a solenoid that can be turned on and off by turning the current on and off

74

## Electromagnetic force

### One of four fundamental forces; the force of attraction or repulsion between two charge particles

75

## Electromagnetic induction

### Process in which current is induced by moving a loop of wire in a magnetic field or by changing the magnetic field

76

## Electron current

### Opposite to conventional current; electron current flows from the negative terminal to the positive terminal

77

## Electrostatic charge

### An accumulated electric charge on an object from a surplus or deficiency of electrons

78

## Magnetic Dipole

### Magnet with two poles (North & South); all magnets are dipoles; cutting one in half creates two dipoles

79

## Magnetic Field Lines

### Invisible lines that map out the magnetic field around a magnet

80

## Magnetic Flux

### The lines of force surrounding a permanent magnet or moving charged particle

81

## Magnetic Forces

### Forces that may attract or repel without touching

82

## Ferromagnetic Materials

### Iron, cobalt, nickel

83

## Magnetic Poles

### The ends, or sides, of a magnet about which the force of magnetic attraction seems to be concentrated

84

## Magnetic Reversal

### The flipping of polarity of the earth's magnetic field

85

## Magnetism

### The force of repulsion (pushing) or attraction (pulling) between poles of magnets

86

## Negative electric charge

### One of the two types of electric charge; repels other negative charges and attracts positive charges

87

## Ohm

### Unit of resistance equivalent to volts/amps

88

## Ohm's Law

### The lat that states that resistance is equal to voltage divided by current (R=VI)

89

## Positive Electric charge

### One of the two types of electric charge; repels other positive charges and attracts negative charges

90

## Power

### The rate of doing work is called power

91

## Power dissipated by a Resistor

### P=IV=I^2R=V^2/R

92

## Repulsion of Electric Charges

### Like charges give positive potential energy (repulsive force). Like charges repel one another.

93

## Resistance

### A material's opposition to the flow of electric current, measured in ohms

94

## Resistors

### Objects that allow charge to flow at a reduced rate (change into heat or light)

95

## Solenoid

### A cylindrical coil of wire that becomes electromagnetic when a current runs through it

96

## Superconductors

### Some materials in which, under certain conditions, the electrical resistance approaches zero

97