1. Charge Model Balloon and Scotch Tape Electroscope Lab

2. Balloon Lab Big Idea: There exist electrical charges which can repel/attract one another.

3. Up and atom! An atom is the smallest unit of a particular element. Atoms are made up of protons (+), neutrons (0), electrons (-).

4. Scotch Tape Lab Big Idea: –(+) and (+) OR (-) and (-) repel –(+) and (-) attract –(+) and (0) OR (-) and (0) attract Why does neutral attract both? –Balloons sim

5. 1.17.14

6. Coulomb’s Law

7. Warm Up/Review Determine how the following net charges on objects would interact: –(+) and (+) –(0) and (-) –(-) and (+)

8. ¢harge Unit$ Compare US Currency $ Electric Charge Smallest Possible Unit Penny $0.01 =1/100 th of a dollar Elementary Charge (1 e) (electron or proton) 1e= 1.60 x 10 -19 C Practical Unit Dollar $1 = 100 pennies Coulomb 1 C = 6.25x10 18 e

9. Elementary Charge Elementary charge- the smallest possible unit of charge (an electron or proton) The net charge on an object MUST BE an integral multiple of this charge. For example: e= 1.60 x 10 -19 C q= (1.5)e= 2.40 x 10 -19 C IS NOT ALLOWED q= (2.0)e= 3.20 x 10 -19 C IS ALLOWED

10. Notes

11. 1.21.14

12. Electric Field vs. Gravitational Field

13. Electric Field The electric field is the direction that a positive test charge would go. The electric field has units of N/C.

14. Electric Field Sketches

15. Partner Quiz Each group gets 2 questions to ask me.

16. Book Sample Problems

17. Book Practice Problems 1, 6, 7, 12, 23, 27, 28

18. 1.23.14 Force and Field Warm Up Question

19. Warm Up What do you conclusively know about the charge of each?

20. Warm Up What do you conclusively know about the charge?

21. Plate Lab

22. Practice

24. 1.24.14: MC Warmup

25. Charging By Induction Lab

26. Faraday Cage

27. http://www.youtube.com/watch?v=Zi4kXgDBFhw

28. Faraday Cage There is no electric field inside of a conductor. All excess charge spreads itself out on the outside of the conductor. This is why you’ll be safe if your car gets struck by lightning. This is also why you get horrible cell phone/radio reception in tunnels and elevators. There can be an electric field inside of an insulator.

29. 1.27.14

30. A conducting sphere has radius R. Which graph represents the Electric field vs. distance from the center of the sphere?

31. Two metal spheres that are initially uncharged are mounted on insulating stands, as show. A negatively charged rubber rod is brought close to, but does not make contact with, sphere X. Sphere Y is then brought close to X on the side opposite to the rubber rod. Y is allowed to touch X and then is removed some distance away. The rubber rod is then moved far away from X and Y. What are the final charges on the spheres?

32. Book Practice

33. STOP Book problems from past two days.