Dry Ice by yurtgc548


									Chapter 3

     Section 2: Energy Can
     change forms but is never

Energy is the ability to do work or to cause
  a change.
Kinetic and Potential Energy are the main
There are several types of Energy, such
  as Nuclear, Mechanical, Thermal,
  Electromagnetic, Sound, and Chemical.
Energy often needs to be transformed in
order to produce a useful form of energy.
   Conservation of Energy

The law of conservation of energy states
  that energy is never created or destroyed.

No matter how energy is transferred or
  transformed, it continues to exist in one
  form or another.
Energy can be transformed in many different ways,
  including from PE to KE and back again.
    Energy Efficiency
A measurement of
  usable energy after
  an energy
  conversion; the
  ratio of usable
  energy to the total
  energy after an
  energy conversion
    Energy Efficiency
ENERGY STAR bulbs use 75
  percent less energy than
  standard incandescent
  bulbs and last up to 10
  times longer

Produces 75 percent less
   heat, so they're safer to
   operate and cuts energy
   costs associated with home
    Unwanted forms of Energy
When energy changes
 forms, the total amount
 of energy does not
 change, but some of the
 energy may convert to
 unusable or unwanted

Usually the unwanted form
  is Heat
Kinetic vs Potential
The picture on the left, because the child is at a higher
point above the ground.
Sun is the indirect source for almost all of Earth’s
energy, including plants, making sugars, as well as
fossil fuels that are burned for electrical energy or
     a law that states that energy can never be
            created or destroyed

applies to

         energy simply changes form
The kinetic energy has been changed into sound, heat,
and then into kinetic energy in the second ball
Energy efficiency is a measure of usable energy after an
energy conversion. Energy-efficient appliances convert
a greater percentage of energy into the desired form.

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