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Nuclear Technology. Energy - the driving force of change Natural Units - atoms, molecules, moles, and electrons Atoms - the tiny wonders Atomic Nuclei - small frontier to explore Radioactive Decay - transmutation of nuclides Particles - frozen energy states
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Nuclear Technology Energy - the driving force of change Natural Units - atoms, molecules, moles, and electrons Atoms - the tiny wonders Atomic Nuclei - small frontier to explore Radioactive Decay - transmutation of nuclides Particles - frozen energy states Nuclides - composite particles of nucleons Nuclear Reactions - changing the hearts of atoms Nuclear Fission - energy for war and peace Nuclear Fusion - an ideal energy source Ionizing Radiation - radiation detection and measurements Radiation Safety - safety in nuclear technology Nuclear Technology - applications of nuclear technology Energy & Nuclear Science
Energy & Nuclear Science The most important aspect of nuclear technology is the large amount of energy involved in nuclear changes, radioactivity, nuclear reactions, radiation effects etc. Thus, the energy concept is very important before we start to explore nuclear science. Nuclear energy associates with mass according to Einstein’s formula, E = m c 2but what does it mean? E = m c2 Energy & Nuclear Science
Energy – driving force of change Change is the only constant in the universe. Changes: winds, rains, storms, thunders, forest fires, earthquakes, waves, plant growth, food decay, ocean tides, formation and melting of ice, combustion, and growing old ... more example please. What are physical and non-physical changes? What causes changes? Heat elasticity gravity electromagnetic wave … Identify changes and energy in everyday events Energy & Nuclear Science
Recognizing energy Energy plays an important partAnd it’s used in all this work;Energy, yest energy with power so great,A kind that cannot shirk. If the farmer had not this energy,He would be at a loss,But it’s sad to think, this energyBelongs to a little brown horse. A school verse by Richard Feynman Nobel laureate for physics Photo of Feynman and Murray Gell-Men Energy & Nuclear Science
Mechanical Work Mass: m kg Acceleration: a m s-2 Force: F = m a N (Newton = kg m s-2) Distance: s m Work: W = F • s J (N m or kg m2 s-2) Potential energy Wp = m g h unites? Kinetic energy Wk = ½ m v 2 work out unites 0.1 kg 1 N Think and deal with quantity of energy Energy & Nuclear Science
Properties of PE and KE PE and KE are state functions – depending on only the final conditions not on how the conditions were arrived (path). Changes of PE and KE depend on only the initial and final conditions, not on the paths. PE and KE are inter-convertible, but not destroyed. Do you know any other properties? Energy in amusement parks Energy & Nuclear Science Explain state functions
The Temperature Concept Objective comparison of energy flow potentials – temperature scales. 0th law of thermodynamicsTwo bodies each equal in temperature to a third body are equal in temperature to each other. Maxwell (19th century) Temperature scales led to the concept of heat The science of heat - thermodynamics. Energy & Nuclear Science
Hot, Cold and Heat What are the differences between hot-cold temperature and heat? Heat, transfers from object to object, elusive. When heat is transferred between objects, their temperatures change. Heat is an extensive property as are electric charge, length, mechanical work, mass, mole, time, etc. Heat is measurable in quantities, units being btu, cal, kcal, J, kJ, kwh, etc.An amount of heat required to raise the temperature of 1.00 g of water from 288.5 to 289.5 K is defined as 1.00 calorie or 4.184 J. Temperatures (hot and cold) indicate potential for heat flow. They are intensive properties as are color, electrical potentials, concentrations heat capacity, pressures, etc. Temperature scales made hot-cold measurements quantitative, but they are not quantities to be added or subtracted. Energy & Nuclear Science Differentiate temperature from heat
The Concept of Heat • Heat is evidently not passive; it is an expansive fluid which dilates in consequence of the repulsion subsisting among its own particlesJoseph Black (1728-1799) • - is a typical additive quantity • is different from hot • inter-convertible to mechanical work (same units) Energy & Nuclear Science
The Energy Concept Inter-conversion of Heat and Work Inter-conversion- discovered unexpectedlyby Ben Thompson (1753-1814) while making cannons. Conversion factor was determined by J. Joule (1818-1889) 1 cal = 4.184 J This entity was called effort, living force, and travail, before the term energy was coined by Thomas Young (1773-1829) Joule in his 20s Energy & Nuclear Science
Energy Heat and work are really energy being transferred. Energy stored in a body is neither heat nor work.Kinetic energies of gases are proportional to their temperature. Once absorbed, the nature of heat has changed. Motion of gas molecules gave rise to pressure - Daniel Bernoulli (1700-1782). Rudolf J.E. Clausius (1822-1888), James Clerk Maxwell (1831-1879), W. Thomson, and Ludwig E. Boltzmann (1844-1906), studied the relationship between temperature and energy of molecular motion. Many elegant theories have been developed as a result. Energy & Nuclear Science
Forms of Energy Other driving forces Benefitchideterminationencouragementinspirationlovelawmotivationresolutionscarcity HeatMechanical work Waves (sound etc) Electromagnetic radiation (waves)Electrical (charge transfer)ChemicalMass (nuclear) What are the properties of energy in these forms and how to evaluate them? Energy & Nuclear Science
Electric Energy Electric energy, EJoulepotential, V Voltcharge, q Coulomb E = V q E = hg m1 J = 1 CV = 1 N m etc Be able to evaluate quantities of electric energy Energy & Nuclear Science
Simple electric energy calculations Electric energy, EJoulepotential, V Voltcharge, q Coulomb E = V q E = hg m1 J = 1 CV = 1 N m etc Potential difference, V, current i ( = q / t ) and resistance R.V = i R (Ohm’s law) Power P, (I/o)P = V q / t = V i( i = current )= R i2 (Joules law) Energy and powerE = P t ( unit kilo-watt-hour) DC and AC Energy & Nuclear Science
eV – a special energy unit Electron-volt, eV, is a very special energy unit, although we have not discussed electricity and electrons yet. Charge of an electron = 1.6022e-19 C (one of the fundamental physical constants). The energy required to increase the electric potential of an electron by 1 V is 1 eV = 1.6022e-19 J (J = C V). Other units used in nuclear energy are keV (1000 eV) MeV (1e6 eV) GeV (1e9 eV) Be able to inter-convert energy quantities in various units Energy & Nuclear Science
What is light? Wave properties? Particle properties? MasslessInterferenceNewton ringdiffraction Law of reflection law of refractionmove in straight line?? Energy & Nuclear Science
Electromagnetic Radiation Electromagnetic radiation is transfer of energy by EM waves via no medium(?). EM waves travel in empty space at constant speed (c = 2.997925e8 m/s constant). EM waves are characterized by wavelength (or frequency ) Light is part of the EM spectrum. EM radiation has a very wide spectrum ( or ). Energy & Nuclear Science
The EM Spectrum The EM Radiation Spectrum Long-wave RadioBroadcast radio bandShort wavelength radioInfraredVISIBLEUltravioletX-raysGamma rays > 600 m 600 - 200 m200 m - 0.1 mm0.1 - 0.0007 mm0.7 - 0.4 um0.4 um - 1 nm1 nm - 0.1 pm0.1 nm Remember the order of these regions Energy & Nuclear Science
The EM Wave Spectrum Energy & Nuclear Science
The Visible Spectrum Double rainbow Energy & Nuclear Science
Photons, E = h Max Planck assumption, E = h , was shown to be true by Einstein’s photoelectric experiment. Speed of light, c = 3e8 m s-1wavelength, frequency of light, = c / Planck constant, h = 6.62619e-34 J senergy of a photon E = h . A photon is a bundle of energy, and it’s like a particle of light. Use wave to show and . Max Planck(1858-1947)Nobel Prize (1918) Energy & Nuclear Science
The Photon Story Max Planck assumption, E = h, was shown to be true by Einstein’s photoelectric experiment. Explain the photoelectric effect. Energy & Nuclear Science
Photon Energy Typical red light, = 4.69e14 s-1 (Hz), = c / = 3e8 m s-1 / 4.69e14 s-1= 640 nm Wave number = 1 / = 1 / 6.40e11 m = 1.56e6 m-1 E = h = 6.62619e-34 J s * 4.69e14 s-1 = 3.1 x 10‑19 J (1 eV / 1.6 x 10-19 J) = 1.9 eV per photon find wavelength or frequency of a violet photon and carry out similar evaluations. Energy & Nuclear Science
Laser Light Amplification by Stimulated Emission of Radiation (LASER) Energy & Nuclear Science
Chemical Energyenthalpy Understand these terms on energy or enthalpy Bond energyenergy of reactionenergy related to temperatureenergy related to states melting, vaporization, phase transitionmass loss in chemical reactions Energy & Nuclear Science
Relative and Zero Masses Special theory of relativity (by Einstein) shows that mass m of a particle with velocity, vrelates to the mass when v = 0, which is called zero mass, mo. Energy & Nuclear Science
Mass and Energy Einstein further showed that the relativistic mass, m, of a particle exceeds its rest mass mo (m = m -mo). The increase in kinetic energy E and increase in mass are related by:E = m c 2 or E = m c 2 Implication:Mass and energy are equivalent. Mass can be expressed in energy unit and vice versa.241800 J = 241800/c 2 = 2.7x10-12 kg = 3 ng Energy & Nuclear Science
Power – rate of energy transfer The SI unit for power P is watt named after James Watt, 1 watt = 1 J s–1 Work out by heart 1 kilowatt-hour = __ J = __ cal = __ BTU Energy & Nuclear Science
The law of Conservation of Energy Energy converts among various forms without any loss or gain. Energy cannot be created nor destroyed. Conversions of energy in various forms have definite rates. These rates never change, and we have energy conversion factors. 1 amu = 1/12th of mass of a C12 atom 1 amu = (12 kg/k mol)/12 = (1 kg/k mol)/(6.022e26 (k mol)-1) = 1.661e-27 kg = 931.5 MeV Energy & Nuclear Science
Some conversion factors 1 eV = 1.602 x 10‑19 J1 eV/molecule = 23045 cal/mol1 MeV = 1.602 x 10‑13 J 1 amu = 1.66043 x 10‑31 J = 931.4812 MeV 1 cal = 4.184 J 1 atm L = 101.3 J 1 J = 1 coulomb‑volt 1 joule = 107 ergs 1 BTU = 252 cal These factors are in the lecture notes. Be able to do unit conversion. Energy & Nuclear Science
Transmitting Energy by Sound Sound intensity (I, watt/m2), level (SIL) isSIL (dB) = SILo + 10 log (I/Io ) At 1000 Hz, the threshold SILo = 0 dB, I0 = 10-12 watt / m2) When I = 1 watt / m2SIL = 120 dB (work out) Comfortable hearing is between 50 and 70 dB, whereas 10 dB is a bel (after A. G. Bell, 1847-1922). A shock wave is due to a sharp difference in pressure from (nuclear) explosions. Shock waves cause serious injuries to ears, and destroy buildings and structures. Energy & Nuclear Science
Thermodynamics Thermodynamics was derived from the Greek words therme (heat) and dynamis (force), intensely studied in the 19th century motivated by the need to convert heat into mechanical work. 0th law: if T of A, TA = T B, TB = TC, then TA = TC 1st law: law of conservation of energy, recognizing internal energy Ein = q – w. 2nd law: not possible for a machine to convert all the heat into work. 3rd law: changes are caused be energy decrease and entropy increase. These laws govern engineering of energy transfer. Energy & Nuclear Science
Energy Resources and Utilization What are possible energy resources? Solar energy Geothermal energy Nuclear energy ??? (class discussion) What technologies are available to utilize these resources? ??? How efficient are some of the technologies? ??? Energy & Nuclear Science
Energy crisis and social problems These issues affect us all, and please apply basics and human natures to solve these problems so your generation will live happily hereafter. Energy & Nuclear Science