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Electricity is
transmitted over
high voltage lines
A Transformer: Converts a current at one voltage into a current in
a separate circuit at a different voltage
 Entirely depends on the relative numbers of coils
A Transformer: Converts a current at one voltage into a current in
a separate circuit at a different voltage
 Entirely depends on the relative numbers of coils
Remember….power is proportional to the square of the current:
P = I2R
The power lines have a small resistance, and so the power lost to
heat will be P = I2R
Need to reduce the current to reduce power lost!
For the Transformer, V(in) x I(in) = V(out) x I(out)
If you go from 120 V to 120,000 V, your current is 1000 times less,
and your power loss is a million times less!!
Demand for Electricity changes over the period of a day
Taum Sauk Reservoir : New Construction
Taum Sauk Reservoir Failure: Dec. 14, 2005
Taum Sauk Reservoir Failure:
Dec. 14, 2005
Taum Sauk Reservoir Failure: Dec. 14, 2005
Taum Sauk Reservoir Failure: Dec. 14, 2005
New Taum Sauk Reservoir
“Standard
Model” of
particles in the
universe
Structure of Neutron and Proton
Structure of Helium
Structure of Helium
Why isn’t the atomic mass 4
(actually 4.0028 amu)?
Structure of Helium
Why isn’t the atomic mass 4
(actually 4.0028 amu)?
 Nuclear Binding Energy!
Why isn’t the atomic mass 4
(actually 4.0028 amu)?
 Nuclear Binding Energy!
Mass of one neutron: 1.00866 amu
Mass of one proton: 1.00728 amu
2 x neutron + 2 x proton = 4.0319 amu
Why isn’t the atomic mass 4
(actually 4.0028 amu)?
 Nuclear Binding Energy!
Mass of one neutron: 1.00866 amu
Mass of one proton: 1.00728 amu
2 x neutron + 2 x proton = 4.0319 amu
SO….Nuclear Binding Energy = 4.0319 – 4.0028 = 0.029 amu
Or, 4.82 x 10-29 kg
But, E = mc2 = (4.82 x 10-29 kg)(3 x 108 m/s)2 = 4.3 x 10-12 J
(Joining the neutrons and protons to make helium nucleus
releases the energy)
Why isn’t the atomic mass 4
(actually 4.0028 amu)?
 Nuclear Binding Energy!
Mass of one neutron: 1.00866 amu
Mass of one proton: 1.00728 amu
2 x neutron + 2 x proton = 4.0319 amu
SO….Nuclear Binding Energy = 4.0319 – 4.0028 = 0.029 amu
Or, 4.82 x 10-29 kg
But, E = mc2 = (4.82 x 10-29 kg)(3 x 108 m/s)2 = 4.3 x 10-12 J
One gram of helium (by fusion) = burning 23 tons of coal
Radioactive Decay: Alpha, Beta, Gamma
Radioactive Decay: Alpha Decay (atom loses helium nucleus)
( = Helium nucleus)
Radioactive Decay: Beta Decay (atom loses electron;
neutron turns to proton)
( = Electron)
Radioactive Decay: Electron Capture (proton turns into
neutron)
Zircon
Crystals:
Good for
trapping in
Uranium and
Lead atoms
(The oldest known zircon crystal in the solar system,
from an Apollo 17 Moon rock: 4.42 billion years old)
Meteorites – oldest rocks on Earth
Allende meteorite (carbonaceous chondrite)
Radioactive cascade
The end result is a stable isotope (for U-238  Pb-206)
A Quick Look at Nuclear Power
U.S. Electricity Sector - Nuclear
• nuclear power is major player
in U.S. electricity industry
– 19. 4 % of electricity
• third major source behind:
– coal: 46.6 %
– natural gas: 21.5 %
• characteristics:
– despite no new plants since
1970s, percentage of
electricity it produces has
been growing
– many plants being re-licensed
for another 20-30 years
– U.S. safety record has been
stellar
• no fatalities, no injuries
A Quick Look at Nuclear Power
U.S. Electricity Sector
A Quick Look at Nuclear Power
Global Electricity Sector
A Quick Look at Nuclear Power
Global Electricity Sector
A Quick Look at Nuclear Power
Global Electricity Sector
A Quick Look at Nuclear Power
Global Electricity Sector
61 new reactors (NEI,
2010)
Taiwan – 2; Iran -1; Pakistan -1
Nuclear Physics
Fundamental Forces
Nuclear Physics
Balancing Nuclear Forces
Nuclear Physics
Binding Curve
Nuclear Physics
Nuclear Transformations
• the nuclear structure of atoms is changed by three different
mechanisms:
– fission: splitting of heavy nuclei into two lighter ones with the
releases of neutrons and energy
• spontaneous
• neutron-induced
– fusion: combining of two nuclei to make a new, heavier nuclei
• new nuclei has less mass than sum of two original nuclei
– radioactive decay: spontaneous emission of either particle or
electromagnetic radiation by nuclei
• particle: alpha, beta, electron capture
• electromagnetic: gamma
• these processes are not influenced by physical conditions,
e.g. pressure, temperature, etc.
Nuclear Physics
Binding Curve
Fission
Fusion
Nuclear Physics
Nuclide Chart
Nuclear Physics
Nuclide Chart