Download Energy & Nuclear Science

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
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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 c2
E=mc2
but what does it mean?
Energy & Nuclear Science
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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
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Recognizing energy
Energy plays an important part
And 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 energy
Belongs 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
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Mechanical Work
Mass: m kg
Acceleration: a m s-2
Force: F = m a N (Newton = kg m s-2)
0.1 kg
Distance: s m
Work: W = F • s J (N m or kg m2 s-2)
1N
Potential energy Wp = m g h unites?
Kinetic energy Wk = ½ m v 2 work out unites
Think and deal with
quantity of energy
Energy & Nuclear Science
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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
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The Temperature Concept
Objective comparison of energy
flow potentials – temperature
scales.
0th law of thermodynamics
Two bodies each equal in
temperature to a third body are
equal in temperature to each
other. Maxwell (19th century)
N
F
C
K
212
100
373.15
12
98
37
310
0
32
0
273.15
-40
233.15
-40
Temperature scales led to the
concept of heat
The science of heat thermodynamics.
Newton (N), Fahrenheit (F), Celsius ( C), and
Kelvin (K) temperature scales.
Energy & Nuclear Science
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Hot, Cold and Heat
What are the differences between hot-cold temperature and heat?
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.
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.
Energy & Nuclear Science
Differentiate temperature from heat
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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 particles
Joseph Black (1728-1799)
- is a typical additive quantity
Is heat a fluid like water?
- is different from hot
- inter-convertible to mechanical
work (same units)
Energy & Nuclear Science
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The Energy Concept
Inter-conversion of Heat and Work
Inter-conversion
- discovered unexpectedly
by Ben Thompson (1753-1814)
while making cannons.
Joule in his 20s
Thermometer
Conversion factor was
determined by J. Joule (18181889) 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)
mgh
Joules experiment demonstrated the
generation of heat by mechanical means.
Energy & Nuclear Science
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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
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Forms of Energy
Other driving forces
Heat
Mechanical work
Waves (sound etc)
Electromagnetic radiation (waves)
Electrical (charge transfer)
Chemical
Mass (nuclear)
Benefit
chi
determination
encouragement
inspiration
love
law
motivation
resolution
scarcity
What are the properties of energy in these forms and how to evaluate them?
Energy & Nuclear Science
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Electric Energy
Electric energy, E Joule
potential, V Volt
charge, q Coulomb
E=Vq
E = hg m
1 J = 1 CV = 1 N m etc
Be able to evaluate quantities
of electric energy
+
+
+
+
+
+
+
-
Electric field
Gravitational field
Energy & Nuclear Science
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Simple electric energy calculations
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 i 2 (Joules law)
Electric energy, E Joule
potential, V Volt
charge, q Coulomb
E=Vq
E = hg m
1 J = 1 CV = 1 N m etc
Energy and power
E = P t ( unit kilo-watt-hour)
DC and AC
Energy & Nuclear Science
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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
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What is light?
Wave properties?
Particle properties?
Massless
Interference
Newton ring
diffraction
Law of reflection
law of refraction
move in straight line
??
Energy & Nuclear Science
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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
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The EM Spectrum
The EM Radiation Spectrum
Long-wave Radio
Broadcast radio band
Short wavelength radio
Infrared
VISIBLE
Ultraviolet
X-rays
Gamma rays
Remember the order
of these regions
> 600 m
600 - 200 m
200 m - 0.1 mm
0.1 - 0.0007 mm
0.7 - 0.4 um
0.4 um - 1 nm
1 nm - 0.1 pm
0.1 nm
Energy & Nuclear Science
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The EM Wave Spectrum
Energy & Nuclear Science
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The Visible Spectrum
Double rainbow
A color pattern seen in an oil film
Energy & Nuclear Science
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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-1
wavelength, 
frequency of light,  = c / 
Planck constant, h = 6.62619e-34 J s
energy of a photon E = h .
Max Planck
(1858-1947)
Nobel Prize (1918)
A photon is a bundle of energy, and it’s
like a particle of light.
Use wave to show  and .
Energy & Nuclear Science
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The Photon Story
Max Planck assumption, E = h, was shown to be true by
Einstein’s photoelectric experiment.
I
N
T
E
N
S
I
T
Y
Kinetic energy
of electron
Rayleigh’s
Prediction
Experimental curve
and Planck’s prediction
Wien’s Law
Threshold
Frequency
Frequency
Explain the photoelectric effect.
Energy & Nuclear Science
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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
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Laser
Light Amplification by Stimulated Emission of Radiation (LASER)
Spontaneous decay
Green
photons
Stimulated decay,
Red laser
Partial mirror
Mirror
Red laser
Green pumping light
Energy & Nuclear Science
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4H + 2O
1469 kJ, bond energy
Understand these terms on
energy or enthalpy
2H2 + O2
484 kJ, energy of
reaction
2H2O(g)373K
81 kJ, energy of
vaporization
2H2O(l)373K
15 kJ, heat
2H2O(l)273K
2H2O(s)273K
Chemical Energy
enthalpy
Bond energy
energy of reaction
energy related to temperature
energy related to states
melting, vaporization, phase
transition
mass loss in chemical reactions
12 kJ, energy of fusion
Energy & Nuclear Science
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Relative and Zero Masses
Special theory of relativity (by Einstein) shows that
mass m of a particle with velocity, v
relates to the mass when v = 0, which is called
zero mass, mo.
m =
mo
v 2
1 - ( )
c
Universal speed
299,792,458 m/s
Energy & Nuclear Science
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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=mc2
Implication:
Mass and energy are equivalent. Mass can be expressed in energy
unit and vice versa.
241800 J = 241800/c 2
= 2.7 x 10-12 kg = 3 ng
Energy & Nuclear Science
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Power – rate of energy transfer
The SI unit for power P is
watt named after James
Watt,
1 watt = 1 J s–1
Power = m g v,
v, pulling velocity
mgh
Work out by heart
1 kilowatt-hour = __ J
= __ cal
= __ BTU
Energy & Nuclear Science
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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
Power = m g v,
v, pulling velocity
mgh
Energy & Nuclear Science
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Some conversion factors
1 eV = 1.602 x 10-19 J
1 eV/molecule = 23045 cal/mol
1 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
These factors are in the
lecture notes. Be able
to do unit conversion.
1 BTU = 252 cal
Energy & Nuclear Science
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Transmitting Energy by Sound
Sound intensity (I, watt/m2), level (SIL) is
SIL (dB) = SILo + 10 log (I/Io )
At 1000 Hz, the threshold
SILo = 0 dB,
I0 = 10-12 watt / m2)
When I = 1 watt / m2
SIL = 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
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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
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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
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Energy crisis and social problems
Level
Demand
These issues affect us all,
and please apply basics and
human natures to solve
these problems so your
generation will live happily
hereafter.
Cost
Arbitrary Coordinate
Energy & Nuclear Science
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