Potential energy is energy stored in an object or system of objects. It can be related to its position, the bonds in its chemical structure, its potential for radioactive decay or even its shape (like in figure 1), to give a few examples. It has the ability or potential to be transformed into more obvious forms like kinetic energy. Potential energy and kinetic energy are what make up mechanical energy.
Imagine lifting a ball off of the ground and holding it in your hand. Energy is required to lift the ball, but after the ball stops moving, the energy used to lift it does not disappear. It has only been converted into gravitational potential energy. Dropping the ball will release the stored energy; as the ball falls, it transforms the potential to a kinetic form as it moves. When the ball hits the ground, the kinetic energy will be absorbed by the ground as heat or released as sound that you can hear.
Likewise if a Slinky is stretched and let go, it will pull itself back to its original shape, that means that there's potential for energy in the Slinky's shape. This is another form of potential energy called elastic potential energy.
Types of potential energy include:
- Gravitational potential energy
- Chemical energy
- Nuclear energy
- Elastic potential energy, also called spring energy
- Electrical potential energy especially in a capacitor
The University of Colorado has graciously allowed us to use the following Phet simulation. Explore this simulation to see how gravitational potential energy and spring potential energy go back and forth and create a changing amount of kinetic energy (hint: click show energy before hanging a mass):
For Further Reading
For further information please see the related pages below:
- Wilson, Tracy. (2014, Aug. 14). How Crossbows Work [Online]. Available: http://science.howstuffworks.com/crossbow2.htm