100 Volts

1. 100 Volts vo,x 0 Volts

2. V(x) 200 150 100 50 Volts 200 Volts 50 x

3. coordinates y z x -200 Volts 200 Volts

4. (note the perpendicular intersections) 10 V 0 V

5. y 10 V 0 V x (line of symmetry is x-axis where y=0)

6. y (where the equipotential line intersects the line of symmetry) 3 V 7 V 10 V 0 V x yields V(x,0) 10 5 x 0

7. V(x,0) 10 5 x (cm) 0 yields Ex(x,0) 150 75 x (cm) 0

8. U(x) potential energy negative slope (FNET to right) unstable equilibrium (FNET = 0) A B x C D positive slope (FNET to left) stable equilibrium (FNET = 0)

9. U(x) potential energy D: FNETto right A: stable equilibrium C: unstable Equilibrium A B x C D B: FNETto left

10. U(x) potential energy A B x C D

11. V(x) electric potential x begin A B

12. Radial electric vector field of a charged conducting circle y + x

13. y y _ + x x

14. y _ x

15. y _ x

16. U(x,y) potential energy dotted lines show constant energy y FNET to right and forward) x

17. U(x,y) potential energy (dotted lines show constant energy: “equipotentials”) y (equipotentials closer where steepest) FNET to right and forward) x

18. V(x,y) electric potential (potential energy per unit charge) dotted lines show constant electric potential solid lines show electric field + y arrow shows electric field direction on positive test charge + x E(x,y)

19. + V(x,y) + + (dotted lines show constant electric potential) y (solid lines show electric field) + (arrow shows force on test charge) x

20. V(x,y) Electrical potential energy per unit charge (dotted lines show constant electric potential while solid lines show electric field) + y (equipotentials closer where steepest) x

21. V(x,y) + (dotted lines show constant electric potential) y (solid lines show electric field) x

22. V(x,y) dotted lines show constant electric potential solid lines show electric field + y x

23. y + x

24. y x

25. y V=4 volts A q B x

26. V=7 volts V=5 volts E=?

27. V=7 volts V=5 volts E=? d = 2 cm

28. Q must be estimated or measured with a protractor to calculate the legs (x and Y components of E). y 100 V/m 57 V/m Q = 35o 82 V/m x

29. 75o 60o 45o 30o 15o 10o

30. V(x,y) dotted lines show constant electric potential solid lines show electric field _ y arrow shows electric field direction on positive test charge + E(x,y) x

31. V(x,y) y + x _

33. + + + + + + + + + + + + + + + + + + + + + + + + + + +

34. V I ACROSS SECTION L

35. + + + + BATTERY BATTERY BATTERY BATTERY ITOTAL IA IB IC ID IE

36. + BATTERY e e e e e e e e e e e e e e e (handle) (spinning paddle wheel) PUMP

37. R R Vsource b c a d R R Vsource e h g f

38. R R resistors in series Vsource Vsource R resistors in parallel R R R Vsource Vsource

39. 3 V 6 W 3V 6 W 6 W

40. + + BATTERY BATTERY current can never flow current may flow (depending on the properties of the ground) the ground the ground

41. + BATTERY the ground

42. _ _ + + 9-VOLT BATTERY 9-VOLT BATTERY

43. + -

44. Unmagnetized iron filings before being placed in magnetic field. N S S N S N S N N S

45. ? S N Needle direction? Draw needle in compass circle. compass

46. STOP PRELAB

47. - + + - - + - + - + - + - - -

48. Uncharged conducting coin grounded to Earth.

49. + - - - - - - - - The presence of positive charge creates an electric field at the coin surface that attracts electrons from the Earth to negatively charge the coin.

50. + - - - - Removing the grounding wire leaves the coin positively charged. The Earth is a giant reservoir of charge, we do not worry about the fact that it has some miniscule amount of excess positive charge.