WHAT CAUSES LIGHTNING?

WHAT CAUSES LIGHTNING

• To understand lightning we first have to understand a bit about atoms and elements.

• What is an atom made up of?

ATOMS

• Atoms are made up of:• Electrons – negatively

charged, orbit the nucleus.• Protons – positively charged,

contained within the nucleus.• Neutrons – neutral charge

(no charge) contained within the nucleus.

ELECTRONS

• Electrons move freely around the nucleus• Their movement is very complicated

• Because they are not bound to the nucleus they can actually transfer from one atom/molecule to another• Some elements like to give up electrons while others like to

gain electrons.• Metals tend to have electrons loosely bound to them allowing transfer

of electrons from atom to atom

POSITIVE AND NEGATIVE CHARGES

• Two atoms with the same charge (both positive or both negative) repel each other• Two atoms with opposite charges (one positive one negative) attract

each other.

• The same can be said on a larger scale, if an object has an overall negative charge it will be attracted to positively charged objects and repel other negatively charged objects.

STATIC ELECTRICITY

•We are going to explore static electricity• Static electricity• Static electricity is the buildup of charge (either positive or

negative) within or on the surface of an object• You build up static electricity when you scuff your shoes

on carpet, it is discharged when you shock someone.

ACTIVITY INSTRUCTIONS• We will be performing a few different experiments to create static

electric charge• Find a group of 2-3 (or I will find one for you)• You will collect the following materials (not yet):• Scotch tape – 2 pieces to start• Metre stick• Two pop cans• Two styrofoam cups• Balloon or pvc(plastic) pipe

ACTIVITY INSTRUCTIONS

• Once you have your materials:• Make two labels with a corner of paper

• One should say T for top• One should say B for bottom

• Put one label on each piece of tape at the end• Stick the tape together, sticky side to smooth side, make sure the

piece labelled T is on top and B is on bottom• Take the pieces of tape together and stick them to your meter stick.

ACTIVITY INSTRUCTIONS

• Now that you have your tape stuck to a meter stick you can keep that meter stick laying across the lab bench.• Take your balloon or PVC pipe, move it close to the pieces of tape

• Record your observations

• Rub your balloon/pvc against your hair or a piece of fur/cloth• Move your object close to the two pieces of tape

• Record your observations

• Do your best to explain your observations based on what we have learned today

ACTIVITY INSTRUCTIONS

• Next take your pop cans and tape them (with new tape) to styrofoam cups

ACTIVITY INSTRUCTIONS

• Take one can and move it close to the pieces of tape, be sure to hold only by the styrofoam cup• Record your observations

• Put both cans together so their bottoms are touching. Label each can as either can 1 or can 2• Have one member of the group hold the styrofoam cups so they do not fall over• Do not touch the cans themselves at any point or you must re-start

• Rub your balloon/pvc against fur/cloth/hair and move it close to the top of can 1 nearest to the side with the tab• While this is being done have one member of your group move the other can

away so they are no longer touching.

ACTIVITY INSTRUCTIONS

• Take each can and have them interact (separately) with your two pieces of tape• Record your observations for each can• What do you think happened/is happening?

• Join another group who is finished with the previous steps.• One group will take their cans and touch them, then set them back down.

• Touch each groups can 1 together then separate them. Be sure to only touch the styrofoam cup.• Have each can interact with the pieces of tape (remember only touch the styrofoam)

• Record your observations

CONTINUE YOUR EXPERIMENT

• Use either balloons or the hollow PVC pipes as they are better than the solid rods.

WHAT HAPPENED? STAGE 1Piece of tape:

Step#

Prediction Result when interacting with object

Bottom (B)

5.   

 

Top (T) 5.   

 

Bottom (B)

6.   

 

Top (T) 6.   

 

Piece of tape:

Step#

Can#

Prediction Result when interacting with can

Bottom (B)

1. 1.     

Top (T) 1. 1.     

Bottom (B)

4. 1.     

Top (T) 4. 1.     

Bottom (B)

4. 2.     

Top (T) 4. 2.     

Piece of tape:

Step#

Can#

Group #

Prediction Result when interacting with can

Bottom (B)

3. 1. 1.    

Top (T) 3. 1. 1.   

 

Bottom (B)

3. 1. 2.    

Top (T) 3. 1. 2.   

 

Bottom (B)

3. 2. 1.    

Top (T) 3. 2. 1.   

 

Bottom (B)

3. 2. 2.    

Top (T) 3. 2. 2.   

 

ELECTRON AFFINITY

• Tendency of an element to donate or receive electrons.

TRIBOELECTRIC SERIES• Tendency of an object to donate electrons or

receive electrons.• Higher on the list give up electrons• Lower on the list receive electrons• Ex. If copper is rubbed against wool copper

will gain electrons while wool will give up electrons

• Ex. If copper is rubbed with polyester polyester will gain electrons and copper will give up electrons

STATIC ELECTRIC CHARGE

• Charging by friction:• Rubbing two objects together to create a transfer of electrons

• See the triboelectric series picture

• Charging by induction:• Charge is induced by placing a charged object near a neutral object.

Electrons are pushed or pulled from one side of an object to another.

• Charging by conduction:• Charge is transferred from one object to another through direct

contact• The overall charge remains the same but is spread over two objects.

CONDUCTORS AND INSULATORS• A conductor is something that allows electrons to move freely

• Example: the pop cans we used allowed us to induce charge by having something strongly charged near them. This would not work with two non-conductors• Wires in electrical cords are good conductors of electricity

• An insulator is something that does not allow electrons to move freely• Ex. Our balloons or plastic rods can build up charge on their surface in

just one place because the electrons can’t move from one spot to another• The rubber around an electrical wire insulates preventing loss of

electrons (and getting a good shock!) to the environment

SO HOW DOES LIGHTNING OCCUR?

• https://www.weathervideohd.tv/wvhd.php?mod=detail&asset=1091

• http://www.mirror.co.uk/news/world-news/force-nature-lightning-strikes-volcano-5344072

HISTORY AND PERSPECTIVES

• Ancient Greeks thought lightning was a weapon used by Zeus to attack his enemies• Thought of places where lightning struck as being sacred• Would erect temples at these sites sometimes

• Norse mythology associates lightning with Thor (yup the same one who shows up in the avengers!) who again used lightning as a weapon• Hindu’s also associated lightning with one of their gods who

used it as a weapon

HISTORY AND PERSPECTIVES

• In Africa one tribe in particular believes that lightning comes from a lightning bird-god• Their medicine men still perform ceremonies to keep storms away from

them• In areas of Russia they would try to summon rain by imitating a

storm• In Europe they would ring church bells to try to scare away the

thunder and lightning

HISTORY AND PERSPECTIVES OF ELECTRICITY• Thales of Miletus ~600BC• Greek philosopher• Discovered static electricity by rubbing amber and fur together, he

found amber could then attract light objects such as feathers• Believed because movement was happening on its own the amber and

feather were in fact alive (so when did life begin?)• That’s about it! Nothing was done with electricity for a very long time

after this• The Greek word for amber was elektron

WILLIAM GILBERT ~ 1600

• First use of the word electricus• Made the first electroscope• Instrument able to detect static electric charge

BENJAMIN FRANKLIN - 1750

• Came up with the idea to fly a kite in a lightning storm to show that lightning is actually a form of electricity.• Showed lightning is electricity• Invented lightning rods• Allow electricity to safely discharge into the ground through a wire

MICHAEL FARADAY 1791-1867

• Demonstrated that a magnetic field can produce an electric field• https://www.youtube.com/watch?v=FehUCQKKRwo• Also found that magnetic fields can rotate light- called the

faraday effect• https://www.youtube.com/watch?v=XhU-nNiAgtI

GEORGE OHM – 1690-1746

• Discovered the relationship between current, voltage and resistance

• Alesandro Volta - 1799• Showed that electricity could be produced by chemical reactions• Invented the first type of battery

• Andre-Marie Ampere – 1775-1836• Developed theories about the relationship between electricity and magnetic fields

THOMAS EDISON 1847-1931

• Regarded as one of the most prolific inventors ever.• However most of his inventions

were actually things his employees invented

• Made great use of Nikola Tesla to improve direct current (DC)

NIKOLA TESLA 1856-1943

• Worked for Thomas Edison in his early career• Invented alternating current electricity (AC)

• More efficient than direct current

• Had a concept for wireless electricity• Thought he could power the whole world

wirelessly

• https://www.youtube.com/watch?v=MgBYQh4zC2Y• Very fun guy to research in your spare time

FIRST NATIONS PERSPECTIVE

• Many First Nations have a story about Thunderbird• Thunderbird is an eagle-like bird, it’s coming announces spring• Both a spiritual and physical being• It’s eyes blink lightning and has a voice of thunder• After the first lightning and thunder of spring elders in some First Nations

begin the first sweat lodge ceremonies of the year.• This is still practiced by some traditional knowledge keepers

• It was believed that lightning striking the ground awoke plants to grow and produce

WHAT IS STATIC ELECTRICITY USED FOR TODAY?• Pollution control:• Smoke particles are

negatively charged as they exit• Collecting plates lining

the smokestack collect the pollutants

OTHER USES

• Electrostatic spray painting• Target material is charged• A dry form of paint is given the

opposite charge and sprayed

• Advantages• Uses less paint • Gives more even coverage

CIRCUIT TYPES

• Open circuit: Any circuit which is not complete, there is no possible path for the electricity to flow completely through the circuit• Closed circuit: A complete circuit, it allows electricity to flow from an

energy source and eventually runs back to that same energy source• Short circuit: A circuit which allows electricity to flow from the

positive to negative ends of a power source while bypassing all functional parts of the circuit. This is typically not done on purpose.• Note: a short circuit is a type of closed circuit

CIRCUIT TYPES

• Parallel circuit: a circuit where there is more than one possible path for the electricity to flow.• Series circuit: a circuit where there is only one possible path

for the electricity to flow.• Combination circuit: Combination circuits contain both

parallel and series sections.

CIRCUIT 1:

• When the battery is attached is this a:• Open circuit• Closed circuit• Short circuit

• Is the circuit a:• Parallel circuit• Series circuit• Combination circuit

CIRCUIT 2:

• When the battery is attached is this a:• Open circuit• Closed circuit• Short circuit

• Is the circuit a:• Parallel circuit• Series circuit• Combination circuit

2 2 11

CIRCUIT 3:

• When the battery is attached is this a:• Open circuit• Closed circuit• Short circuit

• Is the circuit a:• Parallel circuit• Series circuit• Combination circuit

CIRCUIT 4:

• When the battery is attached is this a:• Open circuit• Closed circuit• Short circuit

• Is the circuit a:• Parallel circuit• Series circuit• Combination circuit

CIRCUIT 5:

• When the battery is attached is this a:• Open circuit• Closed circuit• Short circuit

• Is the circuit a:• Parallel circuit• Series circuit• Combination circuit

1,2,3,4,5

1

2

3

4

5

CIRCUIT 6:

• When the battery is attached is this a:• Open circuit• Closed circuit• Short circuit

• Is the circuit a:• Parallel circuit• Series circuit• Combination circuit

A B DC E

CIRCUIT 7:

• When the battery is attached is this a:• Open circuit• Closed circuit• Short circuit

• Is the circuit a:• Parallel circuit• Series circuit• Combination circuit

• Is this a(n):• Open circuit• Closed circuit• Short circuit

• Is the circuit a:• Parallel circuit• Series circuit• Combination circuit

VOLTAGE, RESISTANCE AND CURRENT

• Voltage• Difference in charge between two points - measured in Volts (V)

• The difference in charge is what causes electrons to move

• Current• Measures the flow of electrons through a circuit - measured in amperes (A)

• Resistance• Ability of any material to resist the flow of electrons – measured in Ohms (Ω)

RELATIONSHIPS

• What is the voltage you recorded when there was just 1 light hooked up?• Now look at the second table (where you had two lights

connected) What was the total voltage? What was the voltage of light 1? What was the voltage of light 2?• You can look at these for each set of lights which were

hooked up.

VOLTAGE

• The total voltage should equal the voltage across each light added together• This should roughly equal the voltage of your batteries (each

battery is 1.5 volts, 4 batteries = 6 volts if they were brand new batteries)

RESISTANCE IN SERIES CIRCUITS

• Add up the resistance of lights 1 and 2. How does this compare to the resistance of 1+2?• You can look at the same for each of the sets of batteries

RESISTANCE IN SERIES CIRCUITS

• The total resistance should roughly equal the resistance across the individual lights, much in the same way as voltage adds up.

• Parallel circuits are different, to find total resistance of a parallel circuit:

1 = 1 + 1 + 1 + 1 + 1

Don’t worry you won’t have to calculate this. What it means though is that the resistance when there are 5 lights in parallel is MUCH LOWER than the resistance of a series circuit with those same 5 lights.

R(total) R1 R2 R3 R4 R5

CURRENT IN A SERIES CIRCUIT

• The current in a series circuit is the same at all points.• The current depends on the total resistance of the circuit, not

each individual resistance.

RELATIONSHIP BETWEEN RESISTANCE, VOLTAGE AND CURRENT• Now look at the graph you constructed. • You should have found in your data that voltage remained

relatively constant• It is our controlled variable (the battery determined the voltage)

• As resistance went up (more lights) current went down. • When you have to run up 5 hills you will pace yourself and run slower

than if you only have to run up 1 hill. Electrons pace themselves in much the same way.

RELATIONSHIPS BETWEEN RESISTANCE, VOLTAGE AND CURRENT• Ohm’s law states “The potential difference (voltage) across an

ideal conductor is proportional to the current through it. The constant of proportionality is called the "resistance", R.”• Ohm’s law is typically given in the form:• V=IR This can be re-written I=V/R, or R=V/I• Where V = Voltage (in volts V), I = Current (in Amps A), and R = Resistance (in

Ohms Ω)

• So when given any 2 variables you can determine the third variable.

EXAMPLE 1:

• If you have 3 resistors in series, each resistor has a resistance of 5.0 Ω. The circuit is hooked up to batteries with a total voltage of 12.0

• A) what is the total resistance of this circuit?

• B) what is the current in this circuit?

EXAMPLE 2:

• You have a series circuit with several resistors. The voltage of the batteries used is 4.5 Volts. You measure the current and find that it is 0.50 A. What is the total resistance of the resistors in this circuit?

EXAMPLE 3:

• If you have a series circuit with 4 lights, two lights have resistance of 5.0 Ω, another light has a resistance of 2.5 Ω. The current flowing through this circuit is 0.22 and the voltage of the batteries used is 3.0 V. What is the resistance of the 4th light?

EXAMPLE 4:

• You are working for an electronics company. You have a toy car which uses two 9V batteries (18V total voltage). The car has an electric motor which has a resistance of 14.0 Ω. In order to function properly the current must be 0.8A. To make this circuit work properly you realize you must add a resistor to the circuit. What must the resistance of the additional resistor be in order to obtain the desired current?

POWER TRANSFORMATION

• Electrical energy is one type of energy. We use that energy and transform it to other forms such as:• Mechanical (movement)• Thermal (heat)• Magnetic• Radiant (light)

FOR EXAMPLE:

• We use electrical energy in a light bulb• That energy is transformed into thermal (heat) and radiant (light).

• Incandescent bulbs create a lot of heat while they create light60W

• Compact Fluorescent Bulbs (CFL) create a lot of light and a little bit of heat 15W• Light-Emitting Diode (LED) bulbs create a lot of light and almost no

heat 8W

ENERGY USE

• Electrical companies (saskpower) charge by kilowatt hours (kWh)• In Saskatchewan we are charged 12.63 cents/kWh

• A Watt is simply a measure of energy use/time• A kilowatt hour is how many kilowatts (1000 watts) are used

if a device is on for one hour.

EXAMPLE:

• A 60 Watt bulb uses 60 Watts of power, if it was left on for 3 hours it would use 3x60=180 watt hours of power. Divide this by 1000 to get kilowatt hours(remember our unit conversions from the start of the year?) • 180Watts/1000=0.180 kWh

• If we use that light bulb for 3 hours a day 365 days a year:• 0.180 kWh * 365 days = 65.7kWh * 12.63 cents/kWh=

$8.30/year

ENERGYUSECALCULATOR.COM

• We will use this website to see how much it costs to run your house for a year• Pick the appliance you want to find the yearly cost of, it will

give an approximate energy use, if you scroll down you may find more information for some types of appliances (LED light bulbs, types of game consoles for instance).• You can change the energy cost to 0.1263, you can also

change the hours of usage and the amount of watts used.

RECORD THE COST/YEAR FOR EACH APPLIANCE• How can you reduce your yearly energy consumption (and

thus the cost) within your own household? • Do you think you can make any significant changes to

decrease energy use?• Propose some ways you can reduce the energy use in your household.

• Finally investigate how energy transformation takes place to create mechanical energy from electrical energy.

ENERGY PRODUCTION IN SASKATCHEWAN

• CE9.4 Critique impacts of past, current, and possible future methods of small and large scale electrical energy production and distribution in Saskatchewan

ENERGY PRODUCTION:

• In much the same way we can convert energy from electrical to mechanical, light, heat, or magnetic; we can also convert mechanical, light, heat or magnetic energy into electric energy• Mechanical, light, heat or magnetic energy can be

transformed into electrical energy

ENERGY PRODUCTION AND USE IS INEFFICIENT

CURRENT ENERGY PRODUCTION IN SASKATCHEWAN• Fossil fuels• Coal and natural gas (Boundary Dam near Estevan 824 MW)

• Renewable sources• Windmills (Centennial Wind Power Facility 150 MW)• Hydroelectric dams (Nipawin Hydroelectric station 280 MW)

POWER PRODUCTION: FOSSIL FUELS

• https://www.youtube.com/watch?v=SeXG8K5_UvU• Coal/gas is burned to heat water• Water turns into steam, the steam turns a turbine• The turbine is connected to an electromagnet, when it rotates it

creates electricity (remember the magnet passing over the wire creating current?)• The water is cooled and cycles through again to be re-heated

BOUNDARY DAM CARBON CAPTURE (COAL POWER)• In 2014 one of the generators at Boundary Dam Power

Station was “upgraded” and modified to allow for carbon capture• Up to 90% of the carbon emissions could be captured and re-used• The generator used produces about 150 MW (megawatts) of power

• The total cost is somewhere around $1, 500, 000, 000 (1.5 Billion dollars)• Since its implementation the power station has only been

operational about 40-50% of the time due to maintenance

WINDMILLS

• https://www.youtube.com/watch?v=0Kx3qj_oRCc• Turbines are rotated by wind• the turbine is connected to a magnet which rotates around a magnetic

coil• This generates electrical current

SWIFT CURRENT WIND FARMS (CENTENNIAL WIND POWER FACILITY)• 83 wind turbines• Produces 150 MW of power (enough for 64,000 home)• Cost $272, 000, 000 ($272 million)• Additional funding of $54 million over the next 10 years

• Doesn’t produce carbon• Farmers get paid $2200/year for each turbine on their land• The land can still be farmed/used as pasture.

BOUNDARY DAM VS. WIND FARMS

• Based on cost alone we could have built 5 wind farms instead of boundary dam. This would have been able to power an additional 320,000 homes in Saskatchewan. • No carbon emissions • Noise pollution• Not always reliable

• It doesn’t take a huge change in wind to reduce energy production a lot.

HYDROELECTRIC DAMS

• https://www.youtube.com/watch?v=wvxUZF4lvGw• Water flows through at high pressure turning a turbine• The turbine rotates a magnet which produces current through

a coil of wire.• Ta-da electricity

EFFECTS OF HYDROELECTRIC DAMS

• Hydroelectric dams involve diverting the flow of water• This has had (and continues to have) a large impact on the environment• This impacts many communities where water no longer flows, or some communities

experience flooding• Some first nations communities who rely on traditional fishing, hunting and trapping

methods have been severely impacted• Movement patterns of animals alters greatly due to changes in where their water sources are• Ability to fish is severely altered or destroyed

• http://iportal.usask.ca/docs/Prairie%20Forum/Hydroelectric%20Poer%20and%20Indian%20Water%20(v14no2_1989_pg177-193).pdf

ISLAND FALLS DAM – CHURCHILL RIVER• Near Flin Flon, provides 101 MW of power.• Construction destroyed the ability to fish, hunt and trap effectively in

areas upstream• Some First Nations people found employment at the dam but:

• None ever rose to any significant positions• First Nations employees were forced to use separate break facilities

(washrooms, lunchrooms)

NUCLEAR POWER IN SASKATCHEWAN

• 2/3 of people in Saskatchewan support the idea of a nuclear power plant (poll by the U of S)• 44% of respondants believe that nuclear energy is dangerous• We produce uranium which is used in nuclear power plants

Pros ConsInexpensive to operate Radioactive wasteReliable (gives consistent amounts of energy)

Transportation and mining are not environmentally friendly

Low air pollution (CO2 emissions are low)

Chance of nuclear accidents (Fukushima and Chernobyl)

SOLAR ENERGY

• https://www.youtube.com/watch?v=he_JjrXEfN0• Light comes in, electricity comes out!• I’m writing this down because it’s underlined don’t ruin this

for Mr. Mitchell by saying anything• Light energy is used to move electrons across a gradient

producing electrical current.

ELECTRICAL SAFETY

• https://www.youtube.com/watch?v=tuZxFL9cGkI static electricity• http://

www.dailymotion.com/video/xqcp7y_high-voltage-power-line-repair-by-helicopter_lifestyle • https://www.youtube.com/watch?v=FGoaXZwFlJ4 guy on a wire• https://www.youtube.com/watch?v=3hF5jHl48-U power line on the car• https://www.youtube.com/watch?v=fLVzvMTgGDY oscar worthy• https://www.youtube.com/watch?v=FaB5u0XyiTk reality hits you hard bro• https://www.youtube.com/watch?v=FCSBoOcGFFE reality hits you hard bro the musical

EXAM OUTLINE

• The exam will cover all of electricity except the discussion of power usage in the home and how you can reduce your power consumption.• Physical Science – Characteristics of Electricity (CE) • CE9.1 Demonstrate and analyze characteristics of static electric charge and

current electricity, including historical and cultural understanding. • CE9.2 Analyze the relationships that exist among voltage, current, and

resistance in series and parallel circuits. • CE9.4 Critique impacts of past, current, and possible future methods of small

and large scale electrical energy production and distribution in Saskatchewan.

EXAM OUTLINE CONTINUED

• You should know: the parts of an atom – including specific information about each part• Positive and negative charge, causes, effects on repulsion

and attraction• Static electricity• How it is made (induction, conduction, friction)• Electron affinity (know the trend)• Triboelectric series (be able to use it)

EXAM OUTLINE CONTINUED

• Conductors and insulators• History of electricity including some cultural perspectives • Know the names and their major contributions

• Uses for static electricity – spray painting

EXAM OUTLINE CONTINUED

• Types of circuits• Open, closed, short• Parallel, series, combination

• Predict which lights will turn on in a diagram of a circuit• Voltage resistance and current – definitions

• Relationship between each one• Voltage in series adds up to total voltage• Resistance in series adds up to total resistance• Current in series is the same anywhere in the circuit

EXAM OUTLINE CONTINUED

• Be able to use the formula V=IR to find voltage, resistance or current

• Power transformations- what types of energy can electricity be converted into, what are some examples of devices that do this?• Power production (another type of transformation) – what types of energy can

be converted into electricity, what/how is this done?• How is energy produced in Saskatchewan?

• What has the impact been on various areas?• Possibilities for the future?