Energy
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[edit] Definition
In chemistry and physics, the word energy refers to the ability to do work. (The word work here is used in a technical sense. Work is done when a force acts through a distance.)
Energy can be stored in various forms. Examples include potential energy (due to position in a field such as gravity), kinetic energy (due to motion), chemical energy, and so on.
The S.I. unit of energy is the Joule (J), which is defined as the amount of energy expended in applying a force of one Newton (N) over a distance of one meter (m). However, other units are used in special cases. U.S. heating and air conditioning industry uses the British Thermal Unit (BTU). Electricity use is usually measured in kilowatt-hours (kWh). Chemists traditionally prefer to use the calorie (cal), while dieticians measure food in "Calories" (capital 'C'), a confusing term, since a Calorie is equal to 1000 calories. Particle physicists may measure energy in electron-volts.
[edit] Discussion
Among believers in alternative medicine and the New age, the word energy is used without any regard to its scientific definition. In fact, it's used as a term that can mean practically anything, such as:
- healing energy
- orgone energy
- chi
- whatever supposedly generates the aura
- how active you feel when you get up in the morning
[edit] Energy vs. force
One grievously common error among various pseudoscientific disciplines, especially Free Energy machine claimants, is the confusion between the physical concepts of energy and force.
Many situations in nature involve the exertion of a force without the expenditure of energy. For example, if I put a one-kilogram paperweight onto a table here on Earth, it exerts a force of 9.8 Newtons downward on the table. However, because the paperweight is standing still, the force isn't acting over a distance, so no energy is being expended. Similarly, a planet in a perfectly circular orbit around the sun does not get any closer to or father away from the sun, so although there is a gravitational force holding it in orbit, it is not gaining or losing any orbital energy. Some Flat Earth theorists have claimed that planetary orbits are impossible, because the sun's gravity would have to be constantly expending energy to keep the planet in orbit -- this is a classic case of confusing energy with force.
This website puports to debunk the whole of physics based on only two premises: that energy is conserved; and that force is energy.
A great deal of this confusion comes from the everyday experience of how our human muscles work. For biological reasons, in order for our muscles to exert a force, they must vibrate. Energy is expended, fatigue sets in, etc., merely by the act of a muscle exerting a force -- whether or not the muscle actually moves. You can tire yourself out by pushing on a stone wall that never budges. Thus, it is "common sense" to believe that the exertion of any force also means that energy is also expended. But if you were to replace your muscles with a coiled spring, and mount that coiled spring against the same stone wall, it is very easy to see that a force can be applied to the wall with nothing being "spent" in the process. The spring will stay there exerting a continuous force against the wall until it eventually rusts away, and throughout all that time the potential energy of the spring will remain the same.
