Download Energy Consumption: State and National Perspective

Energy is Fun!
Created for:
Illinois Math & Science Partnerships
Energy Workshop
7/8/2013
Energy comes in many flavors!
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Kinetic Energy
Potential Energy
Thermal/heat Energy
Chemical Energy
Electrical Energy
Electrochemical Energy
Electromagnetic Radiation Energy
Sound Energy
Nuclear Energy
Kinetic Energy (KE)
• Motion!
• An object with kinetic energy (or any other
form of energy) has the ability to do work, e.g.
transferring its energy by pushing or
deforming another object
• KE = ½ m v2
• Example: a flying baseball
Potential Energy (PE)
• In the narrowest sense: gravity can accelerate
an object with potential energy (performing
work on it)
• Note that potential energy depends on a
relationship between two bodies. Potential
energy can be converted to kinetic energy by
acceleration due to gravity.
• PE = mgh
• Example: book on a shelf
Thermal, or Heat Energy
• Actually a microscopic version of kinetic AND
potential energy as molecules bounce off each
other and are alternately attracted to and
repelled from other molecules
• Temperature is a measure of thermal energy
• Example: hot cup of coffee
Chemical Energy
• Actually a microscopic version of potential
energy
• When molecules react with each other and rearrange themselves, they may release or
consume energy
• Example: combustion engine, muscles
consuming glucose
Electrical Energy
• Actually a microscopic version of kinetic AND
potential energy as electrons interact with one
another
• If they are pushed by a force (“voltage”,
“potential” or “emf”), a chain reaction of electron
interactions results – each electron interacting
with and repelling the next one
• Especially true in a conductor, although all
materials conduct to some degree
• Example: electric motor, generator
Electrochemical Energy
• Similar to chemical energy (which is itself a
combination of kinetic and potential energy),
but specifically results in the “flow” of
electrons  electrical energy.
• Example: battery, fuel cell
Electromagnetic Energy
• Electromagnetic radiation, e.g. from the
electromagnetic spectrum
• The entire electromagnetic spectrum can be
considered oscillating, coupled electric and magnetic
fields  waves  radiation has a specific wavelength
and frequency
• Can also be considered particles (photons) 
discrete “packets” of energy
• Example: light from sun
Sound Energy
• Actually a combination of kinetic energy
(vibration) and potential energy (compression)
of particles
• Takes the form of waves, with a specific
frequency
• Example: speakers
Nuclear Energy
• Reactions that involve interactions with a
molecule’s nucleus.
• Atom nuclei are tightly bound  large amount of
potential energy compared to electron
interactions
• Nuclear reactions result in large amounts of heat
and radiation
• E = mc2
• Example: stars (fusion), nuclear reactors (fission)
Forms of Energy
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Kinetic Energy
Potential Energy
Thermal/heat Energy
Chemical Energy
Electrical Energy
Electrochemical Energy
Electromagnetic Radiation Energy
Sound Energy
Nuclear Energy
…but really, these are redundant!
Energy Laws
(1)
Energy comes in many “flavors” or forms.
Kinetic, Potential, Thermal/Heat,
Chemical, Electrical, Electrochemical,
Electromagnetic Radiation, Sound,
Nuclear
Energy Laws
(2)
Energy can be transferred between
objects or systems through various types
of interactions.
Thus, total energy content is not an
intrinsic property of a material, like color
or density.
Energy Laws
(3)
Energy is always conserved; it is never
created or destroyed.
This is known as the First Law of
Thermodynamics
Energy Laws
(4)
Energy can be converted from any form
into any other form, subject only to the
Second Law of Thermodynamics.
Second Law of Thermodynamics: The entropy of an
isolated system never decreases. Equivalently:
natural processes have a preferred direction (Ex:
heat flows in one direction unless work is
performed on the system).