2. 10 電磁 III How is an aurora so thin yet so tall and wide?

3. Sections  磁場  電流與磁場

4. 10-1 磁場  The electric field and the magnetic field  Electromagnet s and permanent magnets

5. 10-1.1 The definition of B

6. The tracks in a bubble chamber

7. The SI unit for B 1 tesla = 1T =1 N/A ‧ m=10 4 gauss

8. Magnetic Field Lines Magnetic vs. electric dipoles A horseshoe and a C-shaped magnets

9. 例 1 A 5.3 MeV proton

10. 10-1.2 Crossed Fields: Discovery of the Electron A cathode ray tube Thomson’s procedure: 設定 E = 0, B = 0, 並記錄光點位 置 開啟電場 開啟磁場, 並調至與電場相等

11. Calculation

12. 10-1.3 Crossed Fields: The Hall Effect By the conduction electrons in copper:

13. 例 2 A cube generator

14. 10-1.4 A Circulating Charged Particle

15. The frequency and angular frequency Helical Paths 頻率與軌跡

16. 極光橢圓圈

17. 例 3 The Mass Spectrometer ( 質譜 儀 )

18. Isotope Separation Centrifuge and diffusion chamber 質譜儀

19. The pitch ( 螺距 ) of the helical path

20. 10-1.5 Cyclotrons and Synchrotrons Fermilab: 6.3km ring ( 迴旋加速器與同步加速器 )

21. The resonance condition: When proton energy > 50Mev: Out of resonance (relativistic effect) A huge magnet (4×10 6 m 2 ) is needed for high energy (500Gev) protons The proton sychrotron at Fermilab can produces 1Tev proton Synchrotrons

22. 10-1.6 Magnetic Force on a Current-Carrying Wire

23. For a wire segment: Magnetic Force

24. 例 4 A length of wire with a semicircular arc

25. Calculation

26. 線圈

27. 10-1.7 Torque on A Current Loop F 2 and F 4 cancel F 1 and F 3 form a force couple

28. 例 5 A galvanometer for analog meters

29. 10-1.8 The Magnetic Dipole The magnetic dipole moments The magnetic potential energy

30. 磁能

31. 10-2 Magnetic Fields due to Currents Conventional rocket EM Rail Gun

32. 10-2.1 Calculating the Magnetic Field due to a current The law of Biot and Savart

33. Magnetic Field Due to a Current in a Long Straight Wire

34. Integration

35. Magnetic Field Due to a Current in a Circular Arc of Wire

36. 例 6 What B does the current produce?

37. 10-2.2 Two Parallel Currents

38. 例 7 The Field Between Two wires

39. 10-2.3 Ampere’s Law Comparing Gauss ’ law and Ampere’s law Ampere’s law

40. The Magnetic Field Outside a Long Straight Wire with Current

41. The Magnetic Field Inside a Long Straight Wire with Current

42. 例 7 A hollow conducting cylinder

43. 10-2.4 Solenoids and Toroids Magnetic Field of a Solenoid ( 螺線管 ) Magnetic Field of a Toroid ( 螺線環 )

44. Magnetic Field of a Solenoid

45. Magnetic Field of a Toroid

46. 磁圍阻核融合反應器 Tokamak Fusion Test Reactor

47. 10-2.5 A Current Carrying Coil and a Magnetic Dipole A current loop and a bar magnet

48. Magnetic Field of a Coil

49. 敬請期待 電磁 IV