Nelson Science Perspectives 9 - Chapter 11 (Electricity)

Front 1

What is electric charge?

Back 1

A form of charge either positive or negative, that exerts an electric force.

Hint 1

Form of charge...

Front 2

What is a neutral object?

Back 2

An object that has an equal amount of protons and electrons.

Hint 2

Equal

Front 3

What is a negatively charged object?

Back 3

An object that had more electrons than protons.

Hint 3

Protons>....

Front 4

What is a positively charged object?

Back 4

An object that has more protons than electrons.

Hint 4

Electrons>...

Front 5

What is static electricity?

Back 5

An imbalance of electric charge on the surface of an object.

Hint 5

Imbalance, surface

Front 6

What is electric force?

Back 6

The force exerted by an object with an electric charge; can be a force of attraction or repulsion

Hint 6

attraction, repulsion

Front 7

What is induced charge separation?

Back 7

A shift in the positions of electrons in a neutral object that occurs when a charged object is brought near it.

Hint 7

shift in electrons, neutral object

Front 8

What is charging by friction?

Back 8

The transfer of electrons between two neutral objects (made from different materials) that occurs when they are rubbed together or come in contact.

Hint 8

transfer of electrons, contact

Front 9

What is the electrostatic series?

Back 9

A list of materials arranged in order of their tendencies to gain electrons.

Hint 9

list of materials, electrons

Front 10

What is charging by conduction?

Back 10

Charging an object by contact with a charged object.

Hint 10

charged object, neutral object

Front 11

What is grounding?

Back 11

Connecting an object to a large body, like Earth, that is capable of effectively removing an electric charge that an object might have.

Hint 11

removing a charge

Front 12

What is a conductor?

Back 12

A material that lets electrons easily move through it.

Hint 12

move easily, electrons

Front 13

What is an insulator?

Back 13

A material that does not allow electrons to easily move through it.

Hint 13

don't move easily, electrons

Front 14

What is charging by induction?

Back 14

Charging a neutral object by bringing a charged object close to, but not touching, the neutral object.

Hint 14

Non-contact, charging, neutral

Front 15

What is electric discharge?

Back 15

The rapid transfer of electric charge from one object to another.

Hint 15

transfer, electrons, fast

Front 16

What is a pith ball electroscope?

Back 16

A device used to detect the presence of electric charges.

Front 17

What is The Law of Electric Charges?

Back 17

Objects that have like charges repel each other.

Objects that have opposite charges attract each other.

Front 18

What is a metal leaf electroscope?

Back 18

A device used to detect electric charges. When a negatively charged object is brought near the electroscope, electrons are transferred into the leaves, which causes them to separate/repel until the object is removed.

Front 19

Attraction Of Neutral Objects to Charged Objects

Back 19

Ex. When a negatively charged object is brought near a neutral object, the electrons in the neutral object move to the other side of which the negative charge is coming from. This is separating the electrons. The protons, however move forward and the objects become attracted as the protons are the closest to the object.

Front 20

Electrostatic Paint Sprayers

Back 20

The paint is given a charge (negative or positive) and the object receiving the paint gets the opposite charge. This causes the paint particles to become attracted to the objects surface, leaving less of a mess and air pollution.

Front 21

Charging Objects by Friction

Back 21

When the object come in contact, the electrons are exchanged. Some atoms are more prone to gain electrons than others. Therefore, one object (the one with the more tendency or becoming negative) become negative and the other (the one with the more tendency or becoming positive) become positive.

Front 22

Electrostatic series

Back 22

Red = Weaker tendencies to gain electrons (aka more positive)

Blue = Stronger tendencies to gain electrons (aka more negative)

Front 23

Charging by conduction - Example

Back 23

A negatively charged object touched a neutral sphere. As a result of the contact, some of the excess electrons on the negative object, transfer to the neutral sphere and become negative.

Hint 23

Negative object, neutral sphere.

Front 24

Charging by conduction - Example 2

Back 24

For example, an object that is positive comes in contact with one that is negative. The charge will even them selves out, meaning some electrons will get distributed to the positive to make it evenly charged.

Front 25

Grounding - Example

Back 25

When a positive charge is getting grounded, electrons move up from the ground to balance out the protons, it then becomes neutral. When a negative charge is getting grounded, the excess electrons travel down into earth until the object is neutral.

Front 26

Electrostatic Precipitators

Back 26

A device that uses the properties of electrostatic charge to remove particles from the air. When smoke passes through the negative charged plates, the particles become negative. They then pass through positive plates, which they stick because opposites attract. The particles fall onto a collection plate allowing to be safely removed.

Front 27

11.3 Lab Report Recap

Back 27

Different materials can build different charges on different objects. This can be influenced by experimental error, such as human error.

Front 28

Conductors

Back 28

•Cannot place a charge on a conductor.

• Water is a conductor (anything other than pure water), as it has ions which allow the current to pass through it.

Front 29

Insulators

Back 29

• In an insulator electrons are tightly bound together, so they are not free to move from one object to another.

• Protects from having charge amounts of charge running through our body.

Front 30

Laser Printers

Back 30

Consists of a drum made of a positively charged photoconductor. The photoconductor only conducts electrons when light shines on it , meaning without light it is an insulator. The light is a laser. The laser draws the image to be printed on a positive drum, causing these areas to become negative. The drum is rolled across positive charged toner particles that are attracted by the negative. The drum is rolled over onto paper that is given a larger negative charge than the drum, the positive toner particles become attracted to the negative paper. The paper is then passed trough a fused to melt then particles and the paper together. It doesn't catch fire as it is a quick process and there is also a fan.

Front 31

Testing for Conductors and Insulators - Lab 11.5

Back 31

When the leaves separate it is a conductor. If it isn't a conductor, the leaves remain the same.

Front 32

Temporary Charge by Induction

Back 32

Induced charge separation - Ex. A negative balloon comes near a neutral wall, the electrons in the balloon repel the electrons in the wall. The positives in the wall become attracted and "move forward". The wall now acts positive because it is attracting the balloon but it is actually neutral.

Front 33

Permanently Charging by Induction

Back 33

Charge permanently by induction by grounding the object. Ex. A negative ebonite rod and a neutral pith ball. When you bring the rod close to the pith ball, the rod repels the ball but then attracts it (induced separation charge). When the electrons are shifted over onto one side ground it. This is taking the electrons out of the pith ball, leaving it charged positive.

Front 34

Electrostatic Lifting Apparatus

Back 34

Giant magnet, given a charge. Object to be lifted given the opposite so it can be picked up

Front 35

Electrostatic Speakers

Back 35

TBD IF NEEDED

Front 36

Electric Discharge

Back 36

• electric discharge moves from the more negative charge to the more positive charge

• greater the imbalance, larger and noticeable the discharge will be.

• air temperature and discharge increases when an electric discharge happens

Ex. A negative door handle and your hand (neutral). You go to team for the handle and receive a shock. This is because the electrons are transferred from the door handle to your hand. After the electric discharge, your hand and the door handle have the same charge.

Front 37

Lightning

Back 37

• very dramatic electric discharge

• occurs because of a charge imbalance between the clouds or clouds and the ground

• excess negative charge at the bottom of the cloud repel the electrons at earth's surface

• electrons on earth's surface move away causing the surface to become positively charged

• the result is a charge imbalance, which leads to an electric discharge in the form of lightning

• as the transfer is fast, the surrounding air becomes superheated, this gives the flash of light and rumbling sound of thunder

• can occur from cloud to cloud, cloud to earth or earth or cloud

• usually travels along the path that most easily transfers electrons to or from the ground

Front 38

Lightning Rods

Back 38

• made of metal like iron and copper

• placed on top of buildings to proving a safe path for lightning to travel to the ground