The Energy Story

  Energy Is Born
  Energy Types
  Energy Changes
  Energy Generation

The Energy Problem

  Conservation of Energy
  Aging of Energy
  Finite Resources
  The Oil "Crisis"
  Energy Pollution
  Discussion Topics

The Energy Solution

  Conserving Electricity
  Appliance Efficiency
  Heating Conservation
  Renewable Energy

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Secret Lives Title - The Energy Story

agig - spring
The Ten Types
Spring Energy


Spring energy is contained in materials and objects that can stretch when a force is placed on them and then later return to their original shape. A graphic of the most well known type of spring is shown below. The spring starts at an unstretched or equilibrium position (x=0). As the spring is stretched from this equilibrium position, spring energy is stored in the spring. The spring can be held until the spring is released and the spring energy is also released. Therefore, spring energy is a form of potential energy.

Many materials and objects can act like springs and contain spring energy that can look very different than the typical spring below. Some other examples of objects that act to store spring energy are: a trampoline, shock absorbers, a sling shot, a stretched rubber band, a bow pulled back with an arrow, the tennis strings in tennis or other racquet as the ball hits them, and spandex in your pants.

stretched spring graphic
You might ask why spring energy isn't included under mechanical energy. It turns out that springs are often used in physics, and that there is a specific equation that has been found for caluculating the spring potential energy. The equation is:
SPE = 1/2 kx squared
where k = spring constant (a measure of how strong the spring is)
x = stretch (how far the spring has stretched from it's equilibrium point)

For more information, check out the websites below.

Elastic Potential Energy Includes a SPE calculator.
Trampolines Trampolines in the olympics and as springs.
Spring Potential Energy This site uses U to stand for SPE (very common).