Catalog of Sites and Images

Lecture: Electrical Current and Circuits

Don't Panic

Hopetoun Falls, Beech Forest, near Otway National Park, Victoria, Australia.

Credit: Wikipedia contributor David Iliff. According to Wikipedia permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version.

Download site: Wikipedia: Image:Hopetoun falls.jpg.

1. Images.

2. alternating current (AC) Images. See also utility frequeqncy (images and maps).

3. alternator Images.

4. American wire gauge Tables. A conventional system which made sense in some early technological age.

5. Avogaro's number Images.

6. battery Images.

7. Ben Franklin Images. Old Ben named positive and negative charges positive and negative. He sort of got them wrong too since it would have been better with the names exchanged for then conventional current would flow the same way as actual current one would think. But he couldn't have known this---out of two choices he ... ---it wasn't the only time he had to guess out of two choices---``We must, indeed, all hang together or, most assuredly, we shall all hang separately.'' ( BrainyQuote).

8. capacitors Images.

9. car battery Images.

10. Charles Proteus Steinmetz (1865--1923) Images. Pioneer of the alternating current and electrification.

11. circuit breakers Images. More than you/I ever wanted to know.

12. circuit symbols Images.

13. coaxial cable Images.

14. copper Images. See occurrence and modern industry for the depleting reserves.

15. cuboid Images.

16. Dracula (circa 1400--) Images.

17. electricity Images.

18. electricity distribution Images.

19. electric circuit No images.

20. electrification No images.

21. electrolyte No images. Equations.

22. electromotive force (emf) No images.

23. electrons Images.

24. energy units No images, but there is a table.

25. ground (electrical) Images.

26. Hall effect Images. It was discovered by American physicist Edwin Hall (1855-1938) in 1879.

27. Hedy Lamarr (1913--2000) Images.

28. High-Voltage Direct Current Images.

29. hydropower Images. A good cartoon of water turbine.

30. impedence matching Images.

31. incandescent light bulb Images. See the section on power which shows that efficiency is typically 7 tl 20 % depending on the bulb power.

32. J.J. Thomson (1856--1940) Images. The lead person in the discovery of the electron using cathode ray tubes which grew up to be the recently obsolescent kind of television set that we-all used to know and love.
    In science and technology, there is usually no one discoverer and inventor, but some large contigent of persons who do some of the work or are working on parallel lines. History picks out one often as the main discoverer---sometimes not very fairly.

33. Kirchhoff's circuit laws Images, but nothing really good.

34. light-emitting diodes Images. These are much more efficient than incandescent light bulbs and may one day replace them. But they have disadvantages too.

35. lightning Images.

36. lightning safety Images.

37. Michael Faraday (1791--1867) Images.

38. Ohm's law Images. Discovered, more or less, by Georg Ohm (1789--1854).

39. Peter Ward No images. See This is how the world ends.

40. resistivity Images and tables.

41. semiconductors Images.

42. short circuit Images.

43. superconductivity Images. The highest T_C conventional superconductor is magnesium diboride (MgB_2) whose T_C=39 K. Remarkably, it's superconducting nature was only discovered circa 2001.

44. SuperGrid No images and not much else yet.

45. Thomas Edison (1847--1931) Images and animations.

46. tungsten Images. See the high melting point of 3422 degrees C.

47. turbine Images.

48. War of Currents Images.

49. watt balance Images.

50. wet cell No images.