This document discusses various topics in physics including nuclear reactions, radioactive decay, stellar nucleosynthesis, nuclear fission and fusion, atomic structure, nuclear power and energy, plate tectonics, earthquakes, tsunamis, and wave mechanics. It provides explanations of physical phenomena like alpha, beta, and gamma radiation, conservation of nucleons, and conservation of energy. It also discusses choices and tradeoffs around different energy sources.

1. Physics in The News: Earthquakes, Tsunamis and Nuclear Power.

2. Work Conservation of Energy Stellar Nucleosynthesis Nuclear Reactions What Radiation is Nuclear Reactors How the Earth Works Wave Mechanics Choices for the Future

3. I like work. It fascinates me. I can sit and look at it for hours. Jerome K. Jerome, English Playwright

4. W=F x t

5. W=F x t

6. Energy is eternal delight. William Blake

7. Conversion of Potential Energy to Kinetic Energy

8. Conversion of Potential Energy to Kinetic Energy

9. Conversion of chemical energy to kinetic energy

10. Conversion of chemical energy to money: Alfred Nobel

11. Conversion of nuclear energy to kinetic energy

12. Conversion of nuclear energy to thermal, then electric energy: where does all this energy come from?

13. Why is compost warm?

14. Nuclear Synthesis and Breakdown

17. Hydrogen and its isotopes are some of the first matter to form: Deuterium and Tritium are less stable, but last a long time.

18. Tritium forms naturally through cosmic rays. It’s radiation is harmless, unless swallowed.

19. 2 4 H He 1 2 E + + + 1 3 n H 0 1 In nuclear fusion, two nuclei with low mass numbers combine to produce a single nucleus with a higher mass number. This happens in stars.

20. Protons are positively charged little particles...they repel each other The neutron helps balance out the positive repulsion via the strong nuclear force. Too many or too few neutrons creates instability. Wait. What’s an isotope? What the hell is a Proton? And what is a Neutron For? How do we know all this?

21. Band of Stability and Radioactive Decay: some atoms are more stable than others….just like people.

22. All science is either physics or stamp collecting. Ernest Rutherford, English Physicist. Nobel Prize in not-Stamp Collecting, 1908.

23. Antoine Henri Becquerel (1852-1908) On the rays emitted by phosphorescence [read before the French Academy of Science 24 Feb. 1896 (ComptesRendus 122, 420 (1896)) translated by Carmen Giunta] In an earlier session, M. Chairman Henry announced that phosphorescent zinc sulfide placed in the path of rays emanating from a Crookes tube augmented the intensity of rays passing through the aluminum. Elsewhere, M. Niewenglowski recognized that commercial phosphorescent calcium sulfide emits rays which pass through opaque bodies. This fact extends to various phosphorescent bodies, and in particular to uranium salts whose phosphorescence has a very brief duration. With the double sulfate of uranium and potassium, of which I have a few crystals forming a thin transparent crust, I was able to perform the following experiment: One wraps a Lumière photographic plate with a bromide emulsion in two sheets of very thick black paper, such that the plate does not become clouded upon being exposed to the sun for a day. One places on the sheet of paper, on the outside, a slab of the phosphorescent substance, and one exposes the whole to the sun for several hours. When one then develops the photographic plate, one recognizes that the silhouette of the phosphorescent substance appears in black on the negative. If one places between the phosphorescent substance and the paper a piece of money or a metal screen pierced with a cut-out design, one sees the image of these objects appear on the negative. One can repeat the same experiments placing a thin pane of glass between the phosphorescent substance and the paper, which excludes the possibility of chemical action due to vapors which might emanate from the substance when heated by the sun's rays. One must conclude from these experiments that the phosphorescent substance in question emits rays which pass through the opaque paper and reduces silver salts.

24. Learning Check

27. http://www.physics.uci.edu/~observat/Physical_Scales.html

28. Stellar NucleoSynthesis: Making everything up to iron!

29. 4Be 1H 2He 6C 2He 1H 1H 6C 2He 4Be 8O 2He 2He Stellar NucleoSynthesis: Making everything up to iron!

31. During a supernova, neutrons bombard heavy ions, building heavy atoms though beta decay. Forged in intense conditions, these atoms are unstable.

32. 14 N 7 Energy + + + 1 4 p He 1 2 Balancing Nuclear Reactions Atomic numbers must balance Mass numbers must balance Use a particle or isotope to fill in the missing protons and neutron Rutherford in 1919 transmutes nitrogen into...

33. 14 17 N O 7 8 Energy + + + 1 4 p He 1 2 Rutherford in 1919 transmutes nitrogen into oxygen.

34. 226 88 4 He 2 Nuclear Reactions: Radium Alpha emission Ra

35. 226 222 Ra Rn 88 86 + 4 He 2 (aka α) Nuclear Reactions: Alpha emission Mass number (A) goes down by 4. atomic number (Z) goes down by 2. Nucleons (nuclear particles… protons and neutrons) are rearranged but conserved

36. 239 239 U Np 92 93 + 0 β -1 Nuclear Reactions: Beta emission Mass number (A) is unchanged. atomic number (Z) goes down up. Here, a neutron breaks down into a proton and an electron.

37. 10 1 n 5 0 + + 4 He 2 (aka α) What happens when we: B Remember: Nucleons (nuclear particles…protons and neutrons) are rearranged but conserved

38. 10 1 B n 5 0 + + 4 13 He N 2 7 (aka α) What happens when we: Nitrogen usually has 7 protons and 7 neutrons…so this has one too few. Nitrogen-13 is a radioisotope of nitrogen used in positron emission tomography (PET). It has a half life of a little under ten minutes, so it must be made at the PET site. A cyclotron may be used for this purpose.

39. 60 Co 27 + 0 β -1 What happens when:

40. 60 60 Co Ni 27 28 + 0 β -1 What happens when: Cobalt 60 has such a short half life you can’t find it in nature. Usually it is created by bombarding a Co-59 atom with a neutron. When it decays, the Nickel atoms are energized and release gamma rays. They used to be employed in radiation therapy for cancer.

41. 60 59 60 60 Co Co Co Ni 27 27 27 28 + 0 β -1 1 + n 0 Cobalt 60 has such a short half life you can’t find it in nature. Usually it is created by bombarding a Co-59 atom with a neutron. When it decays, the Nickel atoms are energized and release gamma rays. They used to be employed in radiation therapy for cancer.

42. 4Be 1H 2He 6C 2He 1H 1H 6C 2He 4Be 8O 2He 2He Stellar NucleoSynthesis: Making everything up to iron!

43. Fission Chain reaction, given enough neutrons. While induced here, it happens naturally, just more slowly.

44. The radioactive decay process can be thought of as a reversal of their formation in the heat of a supernova. As they decay, they release that energy back, due to conservation of Energy

45. The problem with Half life in radioactive elements: it’s a long time. Where to put it when you don’t want it anymore?

46. What’s Uranium Good for? Until 1960, ceramic glazes. Now, since it is so dense (68.4% denser than lead), it ironically make a great radiation shield. And a dense, piercing projectile.

47. Radiation is out there: http://xkcd.com/radiation/

49. So how do we harness this power to make energy?

50. So how do we harness this power to make energy?

51. Three layers of protection: Uranium in a ceramic matrix, in a Zirconum tube, in a Vessel and a Containment building. All the bad stuff stays locked up

52. On site storage is problematic….

53. When containment fails, what happens? Radiation doesn’t get far. But Radioactive particles do.

54. Cesium-137 looks like Potassium to our bodies, and so is harmful when ingested. When a neutron transforms to a proton and a beta particle, the additional proton changes the atom to barium-137. The nucleus ejects the beta particle. However, the nucleus still has too much energy and ejects a gamma photon (gamma radiation) to become more stable.

55. Radioactive Iodine in absorbed by the thyroid, causing cancers. Iodine is an essential element that enables the thyroid gland to produce thyroid hormones: triiodothyronineand thyroxine-- the two key hormones produced by the thyroid gland the “master gland of metabolism”.

56. Usually these reactions only take place quickly when concentrated and purified. This is done via gas centrifuge.

57. Natural nuclear fission reactor, discovered in 1972 at Oklo in Gabon, by French physicist Francis Perrin. http://en.wikipedia.org/wiki/Natural_nuclear_fission_reactor

58. I feel the Earth move under my feet. Carole King

59. Plate Tectonics: Continental Drift

60. An old idea: Antonio Snider-Pellegrini's Illustration of the closed and opened Atlantic Ocean (1858)

61. Mid-Ocean Ridges: this was quack science in 1912 when Alfred Wegner re- proposed the idea. Only in the 1960s was it explained via sea-floor spreading.

62. Mid-Ocean Ridges: HydroThermal Vents as biological oases

63. Nice fossil evidence for Pangaea

64. http://www.washington.edu/burkemuseum/geo_history_wa/The%20Restless%20Earth%20v.2.0.htm The aesthenosphere is kept loose and flowing largely through heat generated by radioactive decay. The material that is decaying is primarily radioactive isotopes of light elements like aluminum and magnesium. This heat source is small on an absolute scale (the corresponding heat flow at the surface out of the Earth is only about 1/6000 of the Solar energy falling on the surface). “Nevertheless, because of the insulating properties of the Earth's rocks this is sufficient to keep the aesthenosphere plastic in consistency.” http://csep10.phys.utk.edu/astr161/lect/earth/tectonics.html

65. Another View: Hot Spots form from convection currents, lasering their way through the Earth’s crust.

66. So the planet is like this: http://www.youtube.com/watch?v=rNcXataE0YM

67. So the planet is like this:

68. Moving continents takes a lot of energy. 2 inches per year. W=F x t

69. When the faults get stuck, energy builds up. Then it releases.

70. This guy may not agree on how much… http://www.youtube.com/watch?v=Co9yzn3ZdWE

71. Water, taken in moderation, cannot hurt anybody. Mark Twain

72. Water waves are an everyday phenomena. http://www.flickr.com/photos/tensorgirl/

73. Waves are about the transfer of energy

74. http://www.nytimes.com/interactive/2011/03/11/world/asia/maps-of-earthquake-and-tsunami-damage-in-japan.html?ref=asia Recall that the amount of energy released here is immense.

75. Until a wave breaks, only the energy moves...the water stays put!

76. Diffusion of energy: higher waves near the epicentre, less further out.

77. The physics of wave height and speed: In the deep ocean, the typical water depth is around 4000 m, so a tsunami will therefore travel at around 200 m/s, or more than 700 km/h. Oddly, Tsunamis slow down as they get to land. http://www.bom.gov.au/tsunami/info/index.shtml

78. Conservation of Energy! If we loose Kinetic Energy, we must gain Potential. The Wave increases in Height, an effect called shoaling. A tsunami with a height of 1 m in the open ocean where the water depth is 4000m would have a wave height of 4 to 5 m in water of depth 10 m.

79. Shoaling: Waves slowing down, getting higher, all due to conservation of Energy.

80. Wave motion around objects – fluid flow and the continuity equation.

81. The garden hose effect

83. The garden hose effect

84. "a pint's a pound the world around" old saw

85. A 480 pound bathtub...

86. Or like getting hit by a fleet of cars…over and over again. (multiple waves!)

87. Gravity, Stars, Nuclear Power, Plate Tectonics, Tsunamis

88. The choices aren’t really all that good…there are compromises with each.

89. Hydroelectric Dams are bad for fish. Wind Power needs to have parts replaced (and it’s bad for birds and bats!).

90. Uranium Mining is not great…but then again, neither is gold mining.

91. Wastes with long lives can be embedded in glass composites with high melting temperatures. This is what they do in France.

92. We have at least 100 years of uranium. Breeder reactors, that make more fissionable bi-products can increase this 2,500 years. Oil can’t do that.

93. So while radiation sucks…it dissipates.

94. Thanks!