1. Day 62 Topic 7: Charges and Circuits

2. Mini Lab…BoC…and next class

3. 3 rd Quarter 5 Full Classes of Topic 7 Q3 Review Day 67 3/25, 3/26 Q3 Exam Day 67 3/27, 3/30 Brunch of Champions Day 68 3/31, 4/1 half day on 4/2? Yeah right; don’t show up because I am not going to be doing important physics that day.

4. Topic 7: Charges and Circuits Today: Review of charges, discussion of basic atomic physics, electric forces. Leaving here today: Lots of atomic stuff: How charges are quantized Rules of charge interactions Charge Separation

5. 1 st Thing To Do Make a list of all things you know/remember/can deduce about a) the makeup of an atom b) how the atom and parts act/react in nature

6. Quick Review: Parts of atom: How do they interact?

7. What is Charge? No idea. It’s a property… Positive or Negative Protons Neutron Electrons

8. A fundamental A fundamental charge is: Charge is a CONSERVED property, which means…

11. If Neutral… Are there protons or electrons in the atom/object? A non-neutral object is Ionized (or an Ion).

12. Basic Charge Rules Like Charges_____________ Opposite charges_____________

13. So in the nucleus Tell a story of how the charges want to move in the nucleus…

14. There is a gravitational attraction (from the mass property…tiny) that keeps the nucleus together There is an electrical repulsion (from the charge property…large) that wants to separate the nucleus There is a Strong Nuclear Force (from the quarks and…., huge) that keeps the nucleus together

15. Tape It Up! Each group follow my tape instructions carefully… Label them A (top) and B (bottom) Explain the charges of A, B and system before and after the ripping. Be detailed, be dramatic.

16. How do the signs of A and B compare? BeforeAfter How does the amount of charge of A and B compare? BeforeAfter Has the amount of mass and/or the elemental property of A and B changed?

17. Tape It Up! How do the signs of A and B compare? BeforeAfter How does the amount of charge of A and B compare? BeforeAfter Charge of system compared to each tape and total, signs, have you changed the physical properties (mass, element) of the tape?

18. Picture… Drawing Tape Lets draw pics before and after, and use the SNF to describe what was exchanged

19. Major Idea The net charge on each object (Q) is measured in Coulumbs (c). Ex: Tape A had a charge of ___________ Those charges felt charges on the tape, and created a net electrical force between them. This Coulumb Force is the Electric Force F E. Can attract or repel

20. Water Watch for a bit Why did the water attract to both + and -? POLAR! The molecule rotated to the attractive part was closer to the rod, and thus had a stronger attraction than the further repulsion.

21. Now get fur and rod and can Charge up the rod using the furry part (fluffier is better). Don’t touch can, bring it close and parallel to the side. Observe…

22. Can drawing and Rod…before

23. Can drawing and Rod…After

24. Summarize