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Flashcards in C10 Terms Deck (58):
1

Stationary electrical charges and the forces that they exert

static electricity

2

Is much stinger than gravity

electrostatic force

3

Like charges repel unlike charges attract

law of charges

4

The net positive or negative charge is measured in?

coulomb (C)

5

The creation of a charged region on a neutral object when exposed to a nearby electrical charge is?

electrical induction

6

A neutral molecule whose electrons have shifted to from positive and negative ends or poles is?

dipole

7

Changes can be detected with what instrument?

electroscope

8

Materials that offer little resistance to electron motion.

electrical conductor

9

A loss of static charges.

electrical discharge

10

A device used to protect buildings from lightning

lightning rod

11

The first capacitor

Leyden jar

12

A devise that stores electrical charges

capacitor

13

Electricity that involves continuously moving charges is called?

electrical current

14

Most TVs contain a large vacuum tube screen called?

cathode-ray tube (CRT)

15

Electrons that have kinetic energy have?

electrical potential energy

16

The flow of positive charges through a conductor is called?

conventional current

17

Current that flows in one direction is called?

direct current

18

The compleat path from the source of electrons to the end is called?

electrical circuit

19

Something that electricity to some other useful form is called?

electrical load

20

Allows you to open or close the circuit.

switch

21

Consists of one or more electromechanical cells that supply electrons released by a chemical reaction.

battery

22

Supplies electrons released by a chemical reaction.

electrochemical cell

23

We measure potential difference with a unit called?

volt (V)

24

The unit in which electrical current is measured.

ampere (A)

25

The resistance to electrical flow is called?

electrical resistance

26

What changes the voltage of the current in an electrical circuit?

resistor

27

Ohm's law state that.

As the size of the voltage changes the current is directly proportional the the voltage change, and the current is directly proportional to the resistance.

28

The unit that resistance is measured in.

ohm

29

The unit of electrical energy used by utilities to sell electricity.

kilowatt-hour (kWh)

30

What is the term for a circuit that has several loads on one wire?

series circuit

31

What is it called when the current branches into parallel paths with the loads on each of the paths?

parallel circuit

32

What is it called when the positive and negative wires touch and the current takes the easiest way to ground?

short circuit

33

What device stops the current when it exceeds a set limit?

overcurrent protections

34

What is the device that detects short circuits?

circuit breaker

35

What is a breaker that detects arcs in a circuit?

arc-fault circuit interrupter (AFCI)

36

Fuse

A metal glass container that melts when the current overloads.

37

What device protects users from electrocution

ground-fault circuit interrupter (GFCI)

38

What causes electrical charges to attract and repel? How does the strength of this force compare to the gravitational force?

The electrostatic force. It is greater than gravity.

39

How many kinds of electrical charges are there? What are they called?

Two. Negative and positive.

40

What makes most every day objects electrically neutral?

They are neutrally charged.

41

What produces a negative charge on an object? A positive charge?

When there is more electrons than protons. When there is more protons than electrons.

42

As like charges move closer together, their lines of force bend farther away from each other and push together into a smaller space. What does this indicate about the size of the forces between them?

They are the same

43

How can you tell that an electroscope has an electrical charge?

The needle will move

44

Describe electrical conductors and insulators and give one example of each. What do we call materials that conduct electricity only under special circumstances

Conductors offer little resistance to electron motion a insulant does not. The copper in a wire is a conductor and the plastic coating on the outside is an insulant

45

What was the first devise to successfully store electrical charges?

The Leyden Jar

46

Name two devices that use static electricity to compleat a task.

An electrostatic precipitator, and a photocopier

47

(True or False) Lightning is a rapid electrostatic discharge.

True

48

Compare the two models of how electrons flow through a conductor

The first is the electron diffusion theory that states that electrons flow from areas of high concentration to areas of low concentration, and the second is the flow of electrons from a point of higher potential energy to a point of lower potential energy

49

What is the name for current that flows in one direction?

Direct current or DC

50

What are the minimum components needed for an electrical circuit to work? What device allows us to control whether or not current flows in a circuit?

The source and the load. A switch

51

What is the unit for electrical potential difference? How is it defined in terms of other SI units?

The volt. It is defined in the formula

1J
1V=-----
1C

52

What is the unit of electrical current?

The ampere (A)

53

What is the unit of electrical resistance?

The Ohm

54

What happens to the current in a short circuit? What can potentially result from a short circuit?

The current bypasses the load. A fire can be the result.

55

What common electrical safety device is designed to prevent electrical fires?

Circuit breakers

56

Give two reasons why circuit breakers are more effective and convenient than fuses.

They trip instantly not allowing a fire to start and they can be reused.

57

Why can a person be shocked to death by less current than is required to start a fire?

Because it does not take much current to stop the heart.

58

What device protects users from electrocution?

Ground-fault circuit interrupters