Chapter 6, Section 3

1. Chapter 6, Section 3 Series and Parallel Circuits: Lighten Up

2. May 29, 2012HW: 6.3 PTG, pg. 621, #1-9, due Fri • LO • Compare series and parallel circuits and learn the language of electricity. • SC • Compare series and parallel circuits • Recognize generator output limit • Modify the Electron-Shuffle model of electricity • Do Now: • 6.2 Group Quiz…to get you thinking again! • Copy LO and SC on new left side page • WDYS/WDYT pg. 614 • Agenda: • Do Now • Investigate Part A

3. Do Now 5/29/12 • WDYS/WDYT pg. 614

4. Investigate Part A • Electron Shuffle • 3 bulbs in parallel • Coulombs go to • Light Bulb 1 if your bday is in Jan, Feb, Mar, Apr • Light Bulb 2 if your bday is in May, June, July, August • Light Bulb 3 if your bday is in Sept, Oct, Nov, Dec • 1-volt battery=1 Joule per Coulomb • Battery: “The battery Voltage is 1 Volt, which equals one joule of energy for each coulomb” • Coulomb: “One coulomb of energy receiving one joule of energy” • Light Bulb: “I just received 1 Joule of energy from that coulomb”

5. Students answer... • Pg. 615 • #4a, b

6. Investigate Part A • Electron Shuffle • 3 Volt battery • 1 Amp current

7. Investigate Part A • Electron Shuffle • 1 Volt battery • 2 Amp current

8. Students answer… • Pg. 616 • #7 a-e

9. April 5, 2011HW: 6.3 PTG, pg. 621, #1-9, due Wed • LO • Compare series and parallel circuits and learn the language of electricity. • SC • Compare series and parallel circuits • Recognize generator output limit • Modify the Electron-Shuffle model of electricity • Do Now: • Pg. 616, #7a-e • Word Web • Agenda: • Do Now • Investigate Part B • Notes • Summary

10. Do Now 5/30/12 • Pg. 616, #7a-e • Word Web

11. Investigate Part B • #1-2 complete in groups, discussion • #3-4 complete in groups, show teacher • #5-6 complete in groups, show teacher, discussion

12. April 7, 2011HW: Study for Test Monday • LO • Compare series and parallel circuits and learn the language of electricity. • SC • Compare series and parallel circuits • Recognize generator output limit • Modify the Electron-Shuffle model of electricity • Do Now: • Period 1: complete 6.3 worksheet you started yesterday • Period 4: Finish Lab • Agenda: • Period 1 • Do Now • Homework • Summary • Period4 • Do Now • Worksheet • Summary

13. Physics Talk • Series Circuit • Total voltage of the battery is divided equally between all bulbs in the circuit. • Coulombs of charge must go through each bulb and drop off joules of energy. • If one bulb is removed, the circuit is open and ALL the bulbs will go out. • 1 volt battery, each bulb will receive 1/3 • Bulbs will appear dimmer

14. Physics Talk • Parallel Circuit • Total voltage provided to each bulb is equal to the voltage of the battery. • Each bulb has a complete circuit from the battery to the bulb and back to the battery • If one bulb is removed, others will remain lit • Bulbs will be equally bright. • Battery will run out more quickly

15. Physics Talk • Series example: • 6 volt battery • How many joules will each bulb get? • Parallel Example • 6 volt battery • How many joules will each bulb get?

16. Physics Talk • What about the current in a parallel circuit? • Current (coulombs/sec) is divided in a parallel circuit • Example: If a parallel circuit has a 3 amp current, each bulb gets one amp of current • How much current would each bulb get if it was a 9 amp circuit?

17. Put it all together! • 9 Volt battery with a 3 amp current • Each bulb receives ____ joules of energy • Each bulb receives ____ amps of current

18. Put it all together! • 9 Volt battery with a 3 amp current • Each bulb receives __9__ joules of energy • Each bulb receives __1__ amps of current • One coulomb will pass each resistor (bulb) every second and drop 6 volts there.

19. Physics Talk • What is a resistor? • What is voltage drop? • A conductor that controls the current in a circuit. • How many joules the coulomb drops off at each resistor

20. The Language of Electricity • 2 kinds of electric charges • Positive (protons) • Negative (electrons) • Like charges (++ or - -) will repel • Protons and electrons have opposite but equal charges • Protons (1+) • Electrons (1-)

21. The language of electricity • Electrons move in circuits and carry the electrical current delivering energy to the bulb • Protons do not flow because they are locked within atoms • Standard “package” of electric charge is called a Coulomb (C)=6.25 x 1018 electrons • Approximately the charge of a bolt of lightning!

22. The language of electricity • Standard rate of flow through a circuit is an ampere (A). • # coulombs that pass through a point in one second

23. The language of electricity • Resistance is the opposition to the flow of electric charge • Resistors are objects that oppose flow of electric charge (light bulb) • Example: High resistance-Tungsten filaments in light bulbs glow as they “rob” energy from passing electrons, causes the tungsten to get hot and glow=LIGHT! • Example: Low resistance-copper wire, electrons transfer little energy so we use copper to conduct electricity in circuits • Measured in Ohms (Ω) • Was the steel wool high or low resistance? Why?

24. The language of electricity • Batteries or generators provide energy to the electrons (coulombs) • Energy given to each coulomb is measured in Volts (V)

25. How do we draw circuits?

26. Essential Questions pg. 620 • What does it mean? • How do you know? • Why should you care? • LO and SC reflection