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College_Physics_2e-WEB_7Zesafu_chunk_2099	planets in our solar system, for example, may be chaotic (we are not certain yet). But they are definitely organized and systematic, with a simple formula describing the orbital radii of the first eight planets and the asteroid belt. Large-scale vortices in Jupiter’s atmosphere are chaotic, but the Great Red Spot is a ...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2100	The emerging field of complexity, like the now almost traditional field of chaos, is partly rooted in physics. Both attempt to see similar systematics in a very broad range of phenomena and, hence, generate a better understanding of them. Time will tell what impact these fields have on more traditional areas of physics...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2101	and was surprised to observe the resistivity of a mediocre conductor like mercury drop to zero at a temperature of 4.2 K. We define the temperature at which and below which a material becomes a superconductor to be its critical temperature, denoted by . (See Figure 34.23.) Progress in understanding how and why a materi...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2102	found to become superconductors, but all had s less than 10 K, which are expensive to maintain. Although Onnes received a Nobel prize in 1913, it was primarily for his work with liquid helium. In 1986, a breakthrough was announced—a ceramic compound was found to have an unprecedented of 35 K. It looked as if much highe...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2103	temperature (about 293 K) would be ideal, but any temperature close to room temperature is relatively cheap to produce and maintain. There are persistent reports of s over 200 K and some in the vicinity of 270 K. Unfortunately, these observations are not routinely reproducible, with samples losing their superconducting...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2104	losing energy to it, making it a superconductor. High- superconductors are more difficult to understand theoretically, but theorists seem to be closing in on a workable theory. The difficulty of understanding how electrons can sneak through materials without losing energy in collisions is even greater at higher tempera...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2105	if answers are found to them. The fun continues. On the Largest Scale 1. Is the universe open or closed? Theorists would like it to be just barely closed and evidence is building toward that conclusion. Recent measurements in the expansion rate of the universe and in CMBR support a flat universe. There is a connection ...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2106	interactions or black holes eating a companion neutron star can be explored. On the Intermediate Scale 1. How do phase transitions take place on the microscopic scale? We know a lot about phase transitions, such as water freezing, but the details of how they occur molecule by molecule are not well understood. Similar q...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2107	want them to be. The answer may have to be indirectly obtained because of the extreme energy at which we think they are unified. 5. Are there other fundamental forces? There was a flurry of activity with claims of a fifth and even a sixth force a few years ago. Interest has subsided, since those forces have not been de...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2108	Glossary axions a type of WIMPs having masses about 10−10 of an electron mass Big Bang a gigantic explosion that threw out matter a few billion years ago black holes objects having such large gravitational fields that things can fall in, but nothing, not even light, can escape chaos word used to describe systems the ou...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2109	between us and the star negatively curved an open universe that expands forever neutralinos a type of WIMPs having masses several orders of magnitude greater than nucleon masses neutrino oscillations a process in which any type of neutrino could change spontaneously into any other neutron stars literally a star compose...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2110	• Galaxies farther away than our local group have, on an average, a recessional velocity given by where is the distance to the galaxy and is the Hubble constant, taken to have the average value • Explanations of the large-scale characteristics of the universe are intimately tied to particle physics. • The dominance of ...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2111	predicted by general relativity but not yet observed, caused by changes in very massive objects. • Quantum gravity is an incompletely developed theory that strives to include general relativity, quantum mechanics, and unification of forces (thus, a TOE). • One unconfirmed connection between general relativity and quant...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2112	other disciplines, such as biological evolution. • Chaos is a field that studies systems whose properties depend extremely sensitively on some variables and whose evolution is impossible to predict. • Chaotic systems may be simple or complex. • Studies of chaos have led to methods for understanding and predicting certa...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2113	eventually fall on a star’s surface. Why then is the sky dark at night? Discuss the commonly accepted evolution of the universe as a solution to this paradox. 7. If the cosmic microwave background radiation (CMBR) is the remnant of the Big Bang’s fireball, we expect to see hot and cold regions in it. What are two cause...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2114	34.2 General Relativity and Quantum Gravity 12. Quantum gravity, if developed, would be an improvement on both general relativity and quantum mechanics, but more mathematically difficult. Under what circumstances would it be necessary to use quantum gravity? Similarly, under what circumstances could general relativity ...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2115	21. Lacking direct evidence of WIMPs as dark matter, why must we eliminate all other possible explanations based on the known forms of matter before we invoke their existence? 34.5 Complexity and Chaos 22. Must a complex system be adaptive to be of interest in the field of complexity? Give an example to support your an...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2116	Problems & Exercises 34.1 Cosmology and Particle Physics 1. Find the approximate mass of the luminous matter in the Milky Way galaxy, given it has approximately stars of average mass 1.5 times that of our Sun. 2. Find the approximate mass of the dark and luminous matter in the Milky Way galaxy. Assume the luminous matt...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2117	it would take to travel 1 Mly at a constant expansion rate of 20 km/s. (b) If deceleration is taken into account, would the actual age of the universe be greater or less than that found here? Explain. 9. Assuming a circular orbit for the Sun about the center of the Milky Way galaxy, calculate its orbital speed using th...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2118	such photons. (c) If the average massive particle in space has a mass half that of a proton, what energy would be created by converting its mass to energy? (d) Does this imply that space is “matter dominated”? Explain briefly. 15. (a) What Hubble constant corresponds to an approximate age of the universe of y? To get a...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2119	16. Show that the velocity of a star orbiting its galaxy in a circular orbit is inversely proportional to the square root of its orbital radius, assuming the mass of the stars inside its orbit acts like a single mass at the center of the galaxy. You may use an equation from a previous chapter to support your conclusion...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2120	that has a mass eight times that of our Sun? Note that stars must be more massive than the Sun to form black holes as a result of a supernova. 23. Black holes with masses smaller than those formed in supernovas may have been created in the Big Bang. Calculate the radius of one that has a mass equal to the Earth’s. 24. ...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2121	25. Construct Your Own Problem Consider a supermassive black hole near the center of a galaxy. Calculate the radius of such an object based on its mass. You must consider how much mass is reasonable for these large objects, and which is now nearly directly observed. (Information on black holes posted on the Web by NASA...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2122	34.6 High-temperature Superconductors 31. A section of superconducting wire carries a current of 100 A and requires 1.00 L of liquid nitrogen per hour to keep it below its critical temperature. For it to be economically advantageous to use a superconducting wire, the cost of cooling the wire must be less than the cost ...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2123	APPENDIX A Atomic Masses Atomic Number, Z Name Atomic Mass Number, A Symbol Atomic Mass (u) Percent Abundance or Decay Mode Half-life, t1/2 0 neutron 1 1.008 665 10.37 min 1 Hydrogen 1 1.007 825 99.985% Deuterium 2 2.014 102 0.015% Tritium 3 3.016 050 12.33 y 2 Helium 3 3.016 030 4 4.002 603 3 Lithium 6 6.015 121 7.5% ...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2124	Atomic Number, Z Name Atomic Mass Number, A Symbol Atomic Mass (u) Percent Abundance or Decay Mode Half-life, t1/2 12 Magnesium 24 23.985 042 78.99% 13 Aluminum 27 26.981 539 100% 14 Silicon 28 27.976 927 92.23% 2.62h 31 30.975 362 15 Phosphorus 31 30.973 762 100% 32 31.973 907 14.28 d 16 Sulfur 32 31.972 070 95.02% 35...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2125	Atomic Number, Z Name Atomic Mass Number, A Symbol Atomic Mass (u) Percent Abundance or Decay Mode Half-life, t1/2 74 73.921 177 36.5% 33 Arsenic 75 74.921 594 100% 34 Selenium 80 79.916 520 49.7% 35 Bromine 79 78.918 336 50.69% 36 Krypton 84 83.911 507 57.0% 37 Rubidium 85 84.911 794 72.17% 38 Strontium 86 85.909 267 ...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2126	Atomic Number, Z Name Atomic Mass Number, A Symbol Atomic Mass (u) Percent Abundance or Decay Mode Half-life, t1/2 134 133.906 696 EC, 2.06 y 56 Barium 137 136.905 812 11.23% 138 137.905 232 71.70% 57 Lanthanum 139 138.906 346 99.91% 58 Cerium 140 139.905 433 88.48% 59 Praseodymium 141 140.907 647 100% 60 Neodymium 142...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2127	Atomic Number, Z Name Atomic Mass Number, A Symbol Atomic Mass (u) Percent Abundance or Decay Mode Half-life, t1/2 202 201.970 617 29.86% 81 Thallium 205 204.974 401 70.48% 82 Lead 206 205.974 440 24.1% 207 206.975 872 22.1% 208 207.976 627 52.4% 210 209.984 163 22.3 y 211 210.988 735 36.1 min 212 211.991 871 10.64 h 8...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2128	Atomic Number, Z Name Atomic Mass Number, A Symbol Atomic Mass (u) Percent Abundance or Decay Mode Half-life, t1/2 99 Einsteinium 254 254.088 019 276 d 100 Fermium 253 253.085 173 EC, 3.00 d 101 Mendelevium 255 255.091 081 EC, 27 min 102 Nobelium 255 255.093 260 EC, 3.1 min 103 Lawrencium 257 257.099 480 EC, 0.646 s 10...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2129	Isotope t 1/2 DecayMode(s) Energy(MeV) Percent -Ray Energy(MeV) Percent 1.33 100% 244.1 d EC 1.12 51% 78.3 h EC 0.0933 70% 0.185 35% 0.300 19% others 118.5 d EC 0.121 20% 0.136 65% 0.265 68% 0.280 20% others 18.8 d 0.69 9% 1.08 9% 1.77 91% 64.8 d EC 0.514 100% 28.8 y 0.546 100% 64.1 h 2.28 100% 6.02 h IT 0.142 100% 99....	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2130	Isotope t 1/2 DecayMode(s) Energy(MeV) Percent -Ray Energy(MeV) Percent 5.32 11% others TABLE B1 Selected Radioactive Isotopes 1552 B • Selected Radioactive Isotopes Access for free at openstax.org APPENDIX C Useful Information This appendix is broken into several tables. • Table C1, Important Constants • Table C2, Su...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2131	Prefix Symbol Value Prefix Symbol Value deka da pico p — — femto f TABLE C4 Metric Prefixes for Powers of Ten and Their Symbols Alpha Eta Nu Tau Beta Theta Xi Upsilon Gamma Iota Omicron Phi Delta Kappa Pi Chi Epsilon Lambda Rho Psi Zeta Mu Sigma Omega TABLE C5 The Greek Alphabet Entity Abbreviation Name Fundamental uni...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2132	Symbol Definition change in energy between the initial and final orbits of an electron in an atom uncertainty in energy difference in mass between initial and final products number of decays that occur change in momentum uncertainty in momentum change in gravitational potential energy rotation angle distance traveled a...	College_Physics_2e-WEB_7Zesafu	pdf
College_Physics_2e-WEB_7Zesafu_chunk_2133	Symbol Definition center of mass quark flavor charm specific heat speed of light kilocalorie calorie heat pump’s coefficient of performance coefficient of performance for refrigerators and air conditioners cosine cotangent cosecant diffusion constant displacement quark flavor down decibel distance of an image from the ...	College_Physics_2e-WEB_7Zesafu	pdf