Composition of Matter/Current, Voltage & Resistance

Question 1

What is a conductor?

Answer 1

A material having 1 to 3 valence electrons that will easily become free electrons to transmit electricity. (materials with low resistance)

Question 2

What is an insulator?

Answer 2

A material having five or more valence electrons that prevents the normal transmission of electricity. (materials with high resistance)

Question 3

What is a semiconductor?

Answer 3

A material having four electrons in the valence band of its atoms and is neither a good conductor or good insulator.

Question 4

What is a neutron?

Answer 4

A particle in the nucleus of an atom that has no electrical charge. However its mass is approximately the same as a proton.

Question 5

What is an electron?

Answer 5

A particle rotating in orbit around the nucleus of an atom. It has a negative electrical charge.

Question 6

What is a compound?

Answer 6

A substance made by combining elements

Question 7

What is an ion?

Answer 7

An atom that has gained or lost an electron

Question 8

What is a valence electron?

Answer 8

An electron in the valence shell of an atom that is loosely bound to the atom and may readily leave its orbit.

Question 9

What is a free electron?

Answer 9

An electron that is dislodged from its atom

Question 10

What is matter?

Answer 10

Anything that has mass and occupies space

Question 11

What is cohesion?

Answer 11

A force that binds molecules together

Question 12

What is solid?

Answer 12

Having hardness and rigidity (length, thickness and breadth)

Question 13

What are elements?

Answer 13

The basic material that goes into the make up of all matter

Question 14

What is mass?

Answer 14

The bulk or size of matter

Question 15

What is energy?

Answer 15

The capacity for doing work. Heat or electricity are examples

Question 16

What is a nucleus?

Answer 16

The center core of an atom

Question 17

What is a valence shell?

Answer 17

The outermost orbit in which electrons may revolve around the nucleus of an atom

Question 18

What is a proton?

Answer 18

The positively charged particle in the nucleus of an atom

Question 19

What is resistance?

Answer 19

The property of a material that opposes the flow of an electric current in a circuit

Question 20

What is a molecule?

Answer 20

The smallest particle into which a compound may be divided and still keep its original identity. (The smallest particle you can have that still maintains the same traits)

Question 21

What is an atom?

Answer 21

The smallest particle of an element that still retains all the properties of the element

Question 22

What is voltage?

Answer 22

Voltage is in the imbalance of electron distribution (or charges), or a difference in charge between two points.

Question 23

What are the six methods of producing EMF?

Answer 23

Magnetic, chemical, friction, heat, pressure and light

Question 24

Conventional current flow can also be referred to as ___ ___.

Answer 24

Hole flow.

Question 25

What is conventional current flow?

Answer 25

It describes the movement of charge through a conductor from the positive source to the negative source.

Question 26

What is electron flow?

Answer 26

It describes the movement of charge through a conductor from the negative source to the positive source.

Question 27

What is static electricity?

Answer 27

The build up of charge in an insulated object.

Question 28

An electric field and free electrons make up a what?

Answer 28

An electric current.

Question 29

When is an electric field or force established?

Answer 29

It is established between two sources of charge that are separated, one positive and another negative.

Question 30

What is electromotive force?

Answer 30

The force that maintains the difference in charge

Question 31

What is the abbreviation for electromotive force?

Answer 31

EMF

Question 32

The symbol for EMF is what?

Answer 32

E

Question 33

What is the unit of measurement for EMF?

Answer 33

Volt, represented by the letter V.

Question 34

What is an electric circuit?

Answer 34

The connection of a source of emf to both ends of a conductor

Question 35

What are the three components a practical electrical circuit consists of?

Answer 35

Source of EMF, conductors and load

Question 36

What is the symbol used for the concept of resistance?

Answer 36

R

Question 37

What is resistance measured in along with its symbol?

Answer 37

Ohms, Ω

Question 38

Describe Ohm's law

Answer 38

The current in a circuit is directly proportional to the EMF applied to the circuit and inversely proportional to the resistance of the circuit.

Question 39

What letter is used to represent electric current?

Answer 39

I

Question 40

What is used to measure electric current?

Answer 40

The unit of measurement for current is an ampere. | Amps, A

Question 41

What is the symbol used to represent quantity of charge?

Answer 41

Q

Question 42

What is quantity of charge measured in?

Answer 42

Coulombs, C

Question 43

What is an electric current?

Answer 43

An electric current is the flow of electrons from a negatively charged point to a positively charged point.

Question 44

What are the two basic components in the universe?

Answer 44

Matter and energy

Question 45

Matter exists and what four physical states?

Answer 45

- solid - liquid - gas - plasma

Question 46

Energy and matter cannot be created or destroyed; however, matter can be changed into energy and energy into matter. True or False

Answer 46

True

Question 47

When matter has low energy or is under pressure it is said to be in what state?

Answer 47

Solid

Question 48

The northern lights is an example of what?

Answer 48

A cool plasma

Question 49

A lightning bolt is an example of what?

Answer 49

A hot plasma

Question 50

Plasma is an ionized gas, | True or False

Answer 50

True

Question 51

The two main properties of matter are what?

Answer 51

Chemical and physical

Question 52

Substances composed of only one type of atom are called what?

Answer 52

Elements

Question 53

Substances composed of more than one type of atom are called what?

Answer 53

Compounds

Question 54

What is required to change matter from one state to another?

Answer 54

Energy

Question 55

How can the physical properties of matter be identified?

Answer 55

Sight, smell, taste, touch or hearing

Question 56

What are the particles rotating around the nucleus of an atom?

Answer 56

Electrons

Question 57

What 2 particles are found within the nucleus of an atom?

Answer 57

Protons and neutrons

Question 58

Neutrons have the same size and mass as a proton but differ in charge. True or False

Answer 58

True

Question 59

The atomic number of an element refers to what?

Answer 59

The number of electrons found in the orbiting paths around the nucleus equals the number of protons in the nucleus (in a neutral state).

Question 60

What is the law of electrical charges?

Answer 60

Unlike charges attract each other, while like charges repel each other.

Question 61

Since protons repel each other they do not stay within the nucleus of an atom. True or False

Answer 61

False, although there is a repelling force between the protons in the nucleus, it is counteracted by an atomic binding force within the nucleus.

Question 62

What is the atomic number for copper and how many electrons are in its valence shell?

Answer 62

29, 1.

Question 63

What is a positive ion?

Answer 63

When an atom has lost electrons.

Question 64

What is the negative ion?

Answer 64

An atom that has gained electrons.

Question 65

If a positively charged particle and a negatively charged particle are close together the force developed between them is one of ___.

Answer 65

Attraction

Question 66

An element is the smallest particle into which a compound can be divided and still keep its original properties. True or False

Answer 66

False, not an element but a molecule

Question 67

Atoms that have the same number of electrons and protons are considered to be what?

Answer 67

Neutral

Question 68

What is the symbol that is used to represent electrical charge?

Answer 68

Q

Question 69

Potential difference may be described as a difference in electron distribution between two points of an electric circuit. True or False

Answer 69

True

Question 70

When a potential difference exists across an open portion of the circuit a current will flow. True or False

Answer 70

False, current will not flow

Question 71

A thermocouple is one method of producing and electromotive force. True or False

Answer 71

True

Question 72

A coulomb is a measure of: Current Amperes Charge or Voltage

Answer 72

Charge

Question 73

Ohm's law, written in the form of an equation, would be what?

Answer 73

``` I=E/R or E=IR or R=E/I ```

Question 74

A generator is a device that uses the magnetic principle to produce electricity. True or False

Answer 74

True

Question 75

The equation that shows the relationship between coulombs and current would be:

Answer 75

``` I=Q/t or Q=It or t=Q/I ```

Question 76

The name used to describe the current that flows from positive to negative in the external circuit is:

Answer 76

Conventional

Question 77

The unit of measurement for resistance is the: Volt Ampere Ohm or Coulomb

Answer 77

Ohm

Question 78

A coulomb is the measure of a certain number of what?

Answer 78

Electrons

Question 79

The symbol used to represent the source voltage of an electric circuit is what?

Answer 79

E

Question 80

The flow of electrons from one point to another is caused by: a) Magnetic attraction b) Repulsion of protons from a negative terminal c) A difference in charge between two points

Answer 80

c, A difference in charge between two points

Question 81

The type of electricity produced by the rubbing together of two materials is called: frictional, conventional, static, electron flow or none of the above

Answer 81

Static

Question 82

What is an example of static electricity?

Answer 82

shoes rubbing against a rug

Question 83

The symbol used to represent a volt drop within an electric circuit is what?

Answer 83

V

Question 84

The unit of measurement for an electric charge is what?

Answer 84

Coulomb

Question 85

And electric field is a force that exist between ____ charges.

Answer 85

different

Question 86

The circuit property that opposes the flow of current within a circuit is called what?

Answer 86

Resistance

Question 87

To have an electric current, you must have an electric field and free electrons. True or False

Answer 87

True

Question 88

A coulomb represents approximately 6.28 x 10¹⁸ of electrons. True or False

Answer 88

True

Question 89

How is voltage measured between two different points?

Answer 89

Voltage is measured across a device, between two conductors or between two separate points along the same conductor.

Question 90

What is current?

Answer 90

The flow of electrons in a conductor that joins the source of negative charge to positive charge and is measured in amperes (A).

Question 91

One volt is the value of the difference in charge that will cause a current of one ampere to flow in a circuit with a resistance of one ohm True or False

Answer 91

True

Question 92

Which electrons are active in the electron flow?

Answer 92

Free electrons

Question 93

The direction of electron flow is determined by what?

Answer 93

The polarity of the source