Electricity & Types of Circuits- Page 4

1. Electricity & Types of Circuits- Page 4 • 7.4- TSW DESCRIBE DIFFERENT FORMS OF ENERGY (ELECTRICITY). • Electricity- the flow of electrons between points having different electrical charges • Direction of Electron Flow- Out of negative end, into positive end • In order for electrons to flow, they need a source (like a battery), a path (a conductor), and this path must form a complete circuit (like a loop)

2. 6.14- TSW DEMONSTRATE THE PROPERTIES THAT CAN BE USED TO IDENTIFY MATTER: CONDUCTIVITY. • Conductor- Material through which electrons can easily flow; conduct electricity well • Most metals are good conductors ex: copper, gold, silver • Current- the flow of electricity in a conductor • Insulator- Material in which electrons are slowed down; keep electricity from moving • Insulators are common: most plastics, wood, glass, leather, etc. • Resistance- The opposition to the movement of electric charges flowing through a material. • An electric current will always flow the path of least resistance

3. Types of Circuits • Circuit- a complete path consisting of electronic elements (conductors, resistors, etc.) through which electric current moves • Switch- A device used to open and close an electric circuit • Simple Circuit- A circuit containing the minimum things needed to have a functioning electric circuit. A simple circuit requires three (3) things: • A source of electricity or voltage (ex. battery or electrical outlet) • A conductive path which would allow for the movement of charges. (ex. wire) • An electrical resistance (resistor), or load; loosely defined as any object that uses electricity to do work (ex. a light bulb, electric motor, heater, speaker, etc.)

4. Broken Simple Circuit  = No light

5. Types of Circuits • Series Circuit- A simple loop with all loads connected in a line • Bulbs share the voltage of the battery • Ex. If the battery is 9V, and there are two bulbs, each bulb gets 4.5 volts • If one light is disconnected, then the other(s) loses power.

6. Types of Circuits • Parallel Circuit- Two loops, both connected to the battery, each with its own load • Bulbs have the full voltage of the battery. • Bulbs in the parallel circuit will be brighter than those in the series circuit. • If one light is disconnected, then the other(s) remains powered.

7. Packet 15, RIGHT Page 6 – EXTRA CREDIT 7.16- TSW DESCRIBE HOW ELECTRICAL CIRCUITS TRANSFER ENERGY TO PRODUCE HEAT, LIGHT, SOUND, AND CHEMICAL CHANGES.

8. Packet 16, Page 4 Static electricity-build up of charges on an object Rub two materials together Electrons pulled off one surface, relocated on other surface Lose electrons  + charge; gain electrons  - charge +/- attract; -/- repel; +/+ repel Static discharge-spark/shock; the loss of static electricity as electric charges move off an object in an attempt to become neutrally charged

9. Track A:Circular Go-Kart track vs.Series electrical circuit • If you add another car to the Go-Kart track, what do you think will happen to the speed of the other cars? • They will slow down because they don’t have any where else to go. • What will happen to the green car if the orange car breaks down on the track? • The green car will have to stop, because there is no way for it to go around.

10. Track B: Figure 8 Go-Kart track vs. Parallel electrical circuit • If you add another car to the track, what do you think will happen to the speed of the other cars? • They will stay at the same speed because they have more options of where they can go. • What will happen to the green car if the orange car breaks down on the track? • The green car will keep going, because there are other ways that it can keep driving around.

11. Electricity/Magnetism Videos • How Electricity is Created from Magnets • 9.15- Start 3.50 end 6.18 • Electricity_and_Magnetism__Current_Electricity 16.58 • Start .36 end 7.29

12. Bellwork: Tuesday 5/29/2012Match the word to its definition Current Electricity Circuit the movement of electrons between points having different electrical charges a complete path consisting of electronic elements (conductors, resistors, etc.) through which electric current moves the flow of electricity in a conductor School House ROCK!

13. Electricity/Magnetism Videos • How Electricity is Created from Magnets • 9.15- Start 3.50 end 6.18 • Electricity_and_Magnetism__Current_Electricity 16.58 • Start .36 end 7.29

14. Electric current flow is necessary for electric shock, but only happens from places of voltage differences • both the bird's feet are at the same voltage • Most birds perch on electrical wires perfectly safely—but there are some dangers. • In particular, large birds such as eagles have wingspans wide enough that they occasionally brush two parallel wires with their wingtips, which completes the electrical circuit and allows electricity to run through the bird's body, killing them.  • This is a serious problem in certain desert areas where the birds use the electrical poles for nesting, due to limited other options.

16. Circuit Review: • Series circuit- An electric circuit with one path for the current to take. • Parallel circuit- An electric circuit with several paths for the current to take. • Flow of electrons  In an electrical circuit, electricity flows from the negative end to the positive end

17. Symbols- Circuit diagrams- Page 5 If Circuits A and C are the same, and Circuits B and E are the same, what is the symbol for: 1). wire, 2). light bulb, 3). battery, 4). switch?

18. Circuit Diagram Symbols- Page 5 7.17- TSW IDENTIFY AND SKETCH THE COMPONENTS OF AN ELECTRICAL CIRCUIT. Wires are shown as straight lines between the different circuit symbols Cell vs. Battery Single battery = cell Two or more cells connected together = battery

19. Circuit Diagrams • Use circuit symbols instead of drawing each component in the circuit. • Always make the wires straight lines • don't be tempted to make them wiggly • the whole point is to make it easier to see what is connected to what • Below: A simple circuit– 1 cell, 1 light, 2 wires. Draw the circuit diagram (using symbols), include arrows to show the direction of electron flow. TIP: Draw the circuit symbols first, and then add all the wires.

20. Series Circuit- 1 cell, 3 bulbs, 5 wires, 1 switch

21. Practice with Circuits DO NOT unscrew the light bulbs to make this work!! • With your group, create a series circuit and a parallel circuit. • Challenge: Try to get a light bulb to light using only: • 1 wire • 1 bulb • 1 battery • Homework: Pg. 6 left side “Will these Circuits work?”

22. Bellwork: Wednesday 5/30/2012 In a series circuit with three bulbs, adding another bulb will make the nearest bulb brighter make some of the bulbs dimmer make all the bulbs brighter make all the bulbs dimmer In a parallel circuit with three bulbs, the bulbs must all be located on the same branch there is only one path for the current to take current from each bulb has its own path the overall resistance increases if a new branch is added. In a series circuit, adding another bulb will make all the bulbs dimmer! In a parallel circuit, current from each bulb has its own path!

23. Housekeeping • Turn in: • Quarter 4 OOPS Pass • FINISHED Study guide DUE MONDAY • Monday- Study Guide Review… Jeopardy? • NOW: Electricity!!

24. Electricity Lab- Page 7 7.15- TSW BUILD A SYSTEM THAT GENERATES ELECTRICITY. - Explain materials and how to use them Read through tasks Explain picking up of materials Draw the circuit, show electron flow, and when the light is lit, raise your hand so you can get signed off!