Science 9: Characteristics of Electricity Unit

Lesson 1: Static Electricity

Begin with activities that revolve around the creating of static electricity. Materials that are needed are balloons, combs, wool, water, carpet, etc.

ZAP IT!Go to a room in the school that is carpeted...the library maybe? Drag your feet and ZAP everyone! What is happening? When is this occurrence more noticeable?

Here is an example of an experiment done with static electricity:

Equipment needed: One balloon (a comb and some plastic hairbrushes will also work well for this,

particularly if you’re worried about the balloon bursting)

A cloth (wool will work best)

Salt

Pepper

Safety glasses

The Digital Bits Science Lab Experiment:

Wear safety glasses for this experiment – you don’t want salt or pepper getting in your eyes.

Mix a small pile of salt and pepper. The challenge here is to separate the salt from the pepper.

It’s easy if you have a balloon: inflate the balloon. Rub the cloth on the balloon, and the balloon will

become negatively charged. This means the balloon will become attracted to objects that have a

different charge. Luckily for us, the salt and pepper fall into this category.

After charging the balloon, hold it above the salt and pepper mixture and slowly bring it closer. You’ll see

the pepper fly up and stick to the balloon, leaving the salt behind. The salt stays put because it’s heavier

than the pepper. This is why you want to move slowly, because if you move too close too fast, the salt

will also fly up and attach to the balloon.

Please copy down the following terminology:

Atom - the smallest part of an element that has all the properties of that element.

Charge - physical property of matter that can give rise to an electric force of attraction or repulsion

Discharge - loss of static electricity as electric charges move off an object

Electrophorus - a device for producing electric charges consisting of a disk that is negatively electridied by friction and a metal plate that becomes charged by induction when placed on the disk

Static Electircity -movement of charges from one object to another without further movement

Turboelectric Series - a current of fluid generator that produces electricity usually for motive power

So, what is happening to create charges and pass them on?

Static electricity is the transfer of electrons from one material to another. You can see the effects of

static electricity using balloons.

Equipment needed:

Two balloons inflated to the same size.

A light stick approximately two feet long (a couple of long matchsticks or chopsticks will do the trick)

Duct tape, masking tape, or some other heavier-duty tape.

String

A piece of cloth (wool works best). Something sock-sized or washcloth-sized will be fine.

The Digital Bits Science Lab Experiment:

If needed, create your “stick”. In the pictures below, I used a couple of long matchsticks, and just duct-

taped them together. The goal is to create a stick long enough to suspend two balloons, and prevent

them from easily touching a wall.

Cut two equal lengths of string, approximately 2 feet long. Tie each balloon to the stick using its own

piece of string. Make sure the baloons are both at the same level.

Tape the stick on to a wall. Inside of a room entrance worked for me. This allows the balloons to extend

into a room, while being held away from the walls.

The balloons may stick to each other slightly, or be repelled slightly, as we see here:

Now, rub one of the balloons with the wool, and let it drop. What happens? It may “bounce” away from

the other balloon. It may stick to it.

Rub the second balloon with the wool, and let it drop. Both balloons should bounce away from each

other. If you’ve built up enough of a charge, one balloon may even bounce off of the other balloon and

stick to the wall:

What’s happening here?

Static electricity is the imbalance of electron charges. When you rub a balloon with the cloth, you’re

actually moving electrons from the cloth to the baloon. The addition of the electrons gives the balloon a

negative charge.

A couple simple rules when dealing with static electricity:

Objects will repel each other if they have the same charge. A balloon with a negative charge will repel

other balloons with a negative charge. This is why the balloons pushed away from each other when we

rubbed them both with the cloth.

Objects will attract each other if they have different charges. A balloon with a positive charge will

attract other things with a negative charge. This is why rubbing a balloon attracts it to the wall – the wall

has a more positive charge, which attracts the balloons more negative charge.

We use balloons in this experiment because they’re very light: the static attraction/repulsion is easier to

see. But you can charge other things, too. See what other things you can make stick to the balloon (hint:

you’ll have good luck with thin, light things, like paper, or hair).

http://www.andybrain.com/sciencelab/2007/11/25/learn-the-basics-of-static-electricity-and-electron-transfer/#more-36

http://www.exploratorium.edu/science_explorer/ro ller.html

empty soda can blown-up balloon your hair

Put the can on its side on a table or the floor -- anyplace that's flat and smooth. Hold it with your finger until it stays still.

Rub the balloon back and forth on your hair really fast.

Move the balloon away from the can -- slowly -- and the can will follow the balloon.

If you move the balloon to the other side of the can, the can will roll in the other direction.

Hold the balloon about an inch infront of the can. The can will start to roll, even though you're not touching it!

How fast will the can roll? How far can you roll it before the can stops? Will it roll uphill?

If you have some friends with cans and balloons, you can have a race across the room or down the sidewalk.

Turn on the faucet in your bathroom or kitchen. Don't run the water too hard, but more than a little trickle. Now rub a balloon on your head and hold the balloon near the water. The stream of water will bend toward the balloon!

Rub the balloon on your head, then pull it away. Your hair will stick out and look really funny. (This can also happen when you comb your hair with a plastic comb.) What if you hold the balloon near your arm? Can you feel the hairs on your arm move? Will it work on doll hair? How about animal fur?

Once you've rubbed the balloon on your head, it will stick to other things -- with no glue. You can stick it to the wall, to the TV, or even to your face!

Why does the soda can roll?When you dry clothes in the dryer,

With Remote Control Roller, basically, you pile up electrons on one thing and use them to attract the protons in something else. When you rub a balloon on your hair, it ends up loaded with electrons. Those electrons can attract the protons in a soda can, the protons in a trickle of water, the protons in your hair, or the protons in a wall.

Why do clothes stick together in the dryer?

The attraction between protons and electrons can also make clothes stick together in the dryer.

different fabrics rub together, and electrons from a cotton sock (for instance) may rub off onto a polyester shirt. That's why clothes sometimes stick together and make sparks when you pull them apart. You may have used antistatic sheets in your dryer. As these sheets bounce around with your clothes, they add a uniform antistatic coating to the fabric. Rather than cotton rubbing against polyester, you've got the antistatic coating on the cotton rubbing against the antistatic coating on the polyester. No electrons rub off-and you don't get any static cling.

A Xerox machine uses static electricity to make copies. When you rub a balloon on your head, the balloon is charged with electricity. Inside a Xerox machine is a plastic drum that is also charged. When you put a piece of paper on the glass, a copy of it goes onto the drum. Where there were dark places on the paper, the static charge on the drum attracts the black plastic toner powder. Then the powdered places go onto a blank piece of paper, and the paper is heated. The toner melts and makes black letters on the new piece of paper.

Lesson 2: How does the charge occur?

Taken and adapted from: http://www.sciencemadesimple.com/static.html

Atoms are made three main particles, the protons and neutrons in the nucleus and the electrons orbiting the nucleus. Protons carry a positive charge, neutrons no charge and electrons carry a negative charge.

The electrical charge of the proton and the electrical charge of the electron actually equal and oppose one another. The charges are often written as +1 (proton) and -1 (electron). If an atom has an equal number of protons and electrons it is neutral and has no charge. If there is a different number of protons and neutrons the atom will carry a charge.

Please remember that the protons and neutrons do not move around, but are held very tightly together in the nucleus. Electrons can be held loosely and can move from one atom to another, thus changing the charge of the atom. If an atom loses electrons and now has more protons, it must have a positive charge because there are more protons. If an atom gains electrons, it will now have more electrons than protons and will have a negative charge.

So, materials that hold their electrons very tightly do not allow electrons to move very easily, making it very difficult for them to take on a charge. These materials are called insulators and an example would be glass. Other materials that hold their electrons loosely allow them to move from atom to atom rather easily. These materials are called conductors and an example would be most metals (copper).

One of the easiest ways to move electrons from one material to another is by rubbing them together. Generally, the more the materials are rubbed together will cause more electrons to transfer creating a greater static charge to be built up. It is believed by scientists that the objects do not have to be rubbed for electron transfer, but simply the contact between the two. Remember static electricity is simply the imbalance between positive and negative charges. Please also remember that opposite charges attract while the same charges will repel each other.

A charged object will also attract a neutral charge, like when a balloon is stuck to the wall after rubbing your hair. When you rub the balloon in your hair, it will pick up extra electrons and will now have a negative charge. If held near a neutral object, it will make the charges in the neutral object move so that the negative charges will move away from the balloon, leaving mostly positive charges nearest the balloon. The balloon will be attracted to the wall and will stick. The process is the same for an object that has a positive charge and an object that is neutral.

So, using this knowledge, how come in the winter when you pull of your toque does your hair stand on end?

http://youtu.be/Z-77IzaXGcg

(Get tips on how to eliminatestatic electricity problems in your home or office.)

Why do you get a shock, or in some cases give a shock after dragging your feet across a carpet?

Lesson 3 – Static Electric Charge Research

To complete this assignment, we will do research on different topics and to create our own packages with all required information about each of the topics. To begin, we have three different columns of topics:

Operation of technologies Contributors DangersAir Filters Thales Lightning RodsFabric Softners Robert Boyle Grounding StrapsAutomotive Painting Benjamin Franklin Grounded PlugsPlastic Wrap Michael Farady FusesVan de Graaff Generator Nikola Tesla Circuit BreakersPhotocopies Georg Ohm

Alessondro VoltaAndre-Maria AmpereJames WimshurstRobert Van de Graf

Operation of Technologies – Please give a quick description of how each of these work and the link to static electricity for each one

Contributors – Please describe their key experiment, as well as what they are noted for (for example, is something named after them, what did they find)

Dangers – Please describe how each functions to reduce the dangers of static electric charge and discharge

So, within your group you will need to research all of the topics above. Please make your answers brief and to the point and feel free to use graphics if needed. You must record all sources that you have used and be sure to source any graphic immediately after using it. All answers must be written in your words.

Groups – Up to 5 students

Assessment Rubric:

Multimedia Project : Static Electric Research

Teacher Name: Mr. Schlosser

Student Name: ________________________________________

CATEGORY 4 3 2 1Requirements All requirements are

met.One requirement was not completely met.

Two to four requirements were not completely met.

More than Four requirements were not completely met.

Content Covers topic in-depth with details and examples. Subject knowledge is excellent.

Includes essential knowledge about the topic. Subject knowledge appears to be good.

Includes essential information about the topic but there are 1-2 factual errors.

Content is minimal OR there are several factual errors.

Organization Content is well organized using headings or bulleted lists to group related material.

Uses headings or bulleted lists to organize, but the overall organization of topics appears flawed.

Content is logically organized for the most part.

There was no clear or logical organizational structure, just lots of facts.

Attractiveness Makes excellent use of font, color, graphics, effects, etc. to enhance the presentation.

Makes good use of font, color, graphics, effects, etc. to enhance to presentation.

Makes use of font, color, graphics, effects, etc. but occasionally these detract from the presentation content.

Use of font, color, graphics, effects etc. but these often distract from the presentaion content.

Sources Source information collected for all graphics, facts and quotes. All documented in desired format.

Source information collected for all graphics, facts and quotes. Most documented in desired format.

Source information collected for graphics, facts and quotes, but not documented in desired format.

Very little or no source information was collected.

Lesson 4 – Conductors and Insulators

Begin by defining the terms:

Conductor - material which permits electrons to flow freely

Dry Cell - a voltaic cell whose contents are not spillable - called also a dry battery

Insulator - material made up of atoms with tightly bound electrons that are not able to flow freely

Have students perform the following activity after some discussion of how we could set up a circuit, and how we would test if something was a conductor or insulator.

You have been selected to design a device that allows you to test whether or not objects are conductors or insulators. Using the materials below, create a device. Make sure you jot down your trials and errors in your Science journal! Good Luck!

Materials

Copper wire (3 pieces stripped at the ends and 30cm in length)one light bulb (flashlight bulb - PR2)one dry cell (Size D)two clean-head thumbtackstwo pencils

In the following lab you will test objects to see whether or not they are conductors or insulators. While you examine these objects, you will need to determine the reasons why they are either a conductor or an insulator.

Make sure you read and then write out the lab before you begin. Remember to follow the safety precautions of working in the lab and have all of your materials prepared before you begin.

TO CONDUCT OR NOT TO CONDUCT...THAT IS THE QUESTION!

Problem or Procedure: Using the devices you created, determine whether or not the objects are conductors or insulators of electricity.

Hypothesis: Rewrite each item and indicate beside it whether or not you think it is a conductor or an insulator of electricity.

Materials:string, nails, pieces of glass. a paper clip, staples, pennies, nickels, dimes, quarters, aluminum, paper, wax crayons, rocks, leather, plastic, styrofoam, cardboard, paper, and an elastic.

Procedure:

1. Create a data chart to record your observations. Your chart should include

an area to list the materials and indicate whether or not an object is a conductor or an insulator and an area to determine why.

2. Draw a diagram of the device you created.3. Using the device you created, test each material.4. Mark the item down as a conductor or an insulator.5. Find 5 other objects to test. Note your predictions before testing them.

Analysis:

1. Which materials are conductors? How do you know for sure?2. Which materials are insulators? How do you know for sure?3. How can you determine if a material is a better conductor than another

material?4. Using the Venn diagram, indicate the similarities and the differences

between conductors and insulators.5. Write a definition for a conductor and for an insulator.

Conclusion:

Answer the problem.

Lesson 5 – Circuit Theory

Begin with the following terminology:

Flow of Electricity – a smooth uninterrupted movement or progress of electric current or power

Simple Circuit – a basic and simple, complete path through which electricity can flow

A simple circuit has the following requirements:

1. Source of electricity - provides energy and a supply of electrons for the circuit … Battery

2. A conductive path - conductor - provides a path for the current …Wires

3. an object which requires electricity to do work - converts electrical energy into another form of energy … Bulb

A SIMPLE CIRCUIT

PROBLEM: Why does electricity not flow from the outlets in your home at all times?

HYPOTHESIS:

MATERIALS: dry cell, flashlight bulb, wire

PROCEDURE:

1. Connect one wire from a terminal on a dry cell to a small flashlight bulb.2. What happens?3. Connect another wire from the bulb to the other terminal on the dry cell.4. What happens?

CONCLUSION: Develop an answer to the problem. Make sure you explain why in your response.

Closed Circuit – a circuit with a complete pathwayOpen Circuit – a circuit with an incomplete pathwayComplete Circuit – a circuit in which the current can flow in a circular patternShort Circuit – A circuit in which most of the current flow around or away from another path in the circuit. Accidental short circuits can cause very strong current to flow and possibly damage or overheat a circuit.

How does the particle theory of matter and electron transfer help explain the flow of charge?

Lesson 6 – Building Circuits

Begin with the handout Electronic Diagrams to learn how to draw electronic diagrams. Please note that these are very basic diagrams that we are drawing to learn the basics of drawing.Besides the basic symbols, there are a few more to know. Here is a list of all the symbols you will be required to know:WireBatteryOpen SwitchClosed SwitchLightVoltmeterGalvanometerAmmeter

Parallel Circuit – a circuit in which different parts are on separate branches; if one part does not operate properly, current can still flow through others

Series - circuit in which all parts are connected one after another; if one part fails to operate properly, the current cannot flow

We will now build circuits with the use of the task cards to create circuits in parallel and in series. Make sure you draw what you create on your individual data sheet that you will produce and answer the questions at the end of the activities.

We will print off the following worksheet and complete it:

http://www.zerobio.com/central/cells_series_parallel.pdf

Lesson 7 – Ohm’ s LawOhm’s Law is a measure of the ratio of the voltage(V) to the current (l)to determine the resistance (R). If the resistance is high, so is the level of energy gain which is evident in things like light bulb filaments and toaster wire. The table shows each quantity and the unit used:

http://www.allaboutcircuits.com/vol_1/chpt_2/1.html

The formula can be written as: R = V l

We will solve a couple of examples:

I = 45 mA, R = 3.0 kΩ; V = V = 45 V, R = 4.7 kΩ; I = V = 14 V, I = 110 A; R =

Please complete the Ohm’s Law Practice Questions.http://isite.lps.org/wsmith3/web/Ohm.pdf

Lesson 8 - Electricity can be transformed …

How does electricity become the light we are seeing? How does it become heat? Please read the following:

http://www.edquest.ca/pdf/sf94-4notes.pdf

What are the four types of energy?

Lesson 9 – Use of Electricity

Begin with Defenitions:

Ampere (amp): the unit used to measure electric current; the symbol is A

Current: flow of charge

Electric Power: Voltage times Curent (P=VxI) P=power, V=voltage and I=current in amperes

Galvanometer: device that uses an electromagnet to detect small amounts of current

Voltage: potential difference; energy carried by charges that make up a current

Wattage: amount of power expressed in watts

In small groups, you are going to look at a cool light bulb. (That means a light bulb that is not hot from use!) Are there any words written on it? What do you think those words mean?

ELECTRIC POWER

Read the information on electric power and how it measures the work or energy electricity provides.

Power means strength, or force or energy. To a scientist, power is the rate at which work is done or energy is used. Electric power is a measure of the rate at which electricity does work or provides energy.

For example, the power used to run a dishwasher is 2300 watts.

Watts (W) are the units in which electric power is measured.

Now remember, electric power measures the rate at which electricity does work or provides energy.

Electric power can be calculated by using the following equation: Power = Voltage x Current or P = V x 1

Another way to put it is Watts = Volts x Amperes

Think about a light bulb... The electricity in your home is 120 volts. The light bulb itself operates at o.5 ampere.

According to the equation for power, multiplying these two numbers gives the bulb's wattage, which in this case is 60 watts.

The wattage tells you the power of the bulb, or the rate at which energy is being delivered.

THE HIGHER THE WATTAGE...THE BRIGHTER THE BULB...AND THE MORE EXPENSIVE TO RUN.

The table below shows the power used by some common appliances. Which appliance would use the greatest amount of electric energy if operated for one hour? Which appliance listed uses the least number of watts?

APPLIANCE POWER USED(WATTS) APPLIANCE POWER USED

(WATTS)Refrigerator/Freezer 600 Dishwasher 2300Toaster 700 Range/Oven 2600

Hair dryer 1000 Color television 300

Microwave oven 1450 Radio 100Clock 3 Clothes dryer 4000

Your task will be to determine the amount of power you use in 48 to 72 hours by creating a table and keeping track of at least 10 different items used in your house and the amount of power that each uses. We will then multiply by the value of power (in town or city $0.1061/Kwh, rural is $0.1084/Kwh) to determine your cost over the time period. We can get the power usage off of most items by looking at the back or the tag that is on it, often on the back.

Item Voltage Current Power Power Time Usage CostVolts Amps Watts Kw Hours Kwh 0.1084/Kwh Total

These links can be used to help you determine the amount of power some items will draw:

http://www.energysavers.gov/your_home/appliances/index.cfm/mytopic=10040

http://www.saskpower.com/calculator/residential?open&linkid=cost_calculator_redirect

Lesson 10 – How do Motors work?

Read the pages at the following link:

http://www.edquest.ca/pdf/sf94-6notes.pdf

Lesson 11 – How do batteries work?

http://www.edquest.ca/pdf/sf94-5notes.pdf

How does this effect new technology things like electric cars?

Lesson 12 – The Future

Please look at the following link:

http://www.edquest.ca/pdf/sf94-8notes.pdf

Knowing what you know, if you had choice to use one future energy source, what would you choose? Why would you choose it? Please write a me a short one page essay that will outline what you believe and will attempt to convince others to believe as well. You will be evaluated on the following criteria:

Intro paragraph with clear statement of belief 1 mark

Concluding paragraph 1 mark

3 points that support your belief, each in own 6 marks (2 for each point)

paragraph with own support

Grammar (-.25 per error) 1 mark

Convince me!!!! 1 mark