Energy of Friction
According to the law of conservation of energy, no energy is destroyed due to friction, though it may be lost to the system of concern. Energy is transformed from other forms into heat. A sliding hockey puck comes to rest because friction converts its kinetic energy into heat. Since heat quickly dissipates, many early philosophers, including Aristotle, wrongly concluded that moving objects lose energy without a driving force.
When an object is pushed along a surface, the energy converted to heat is given by:
where
- is the normal force,
- is the coefficient of kinetic friction,
- is the coordinate along which the object transverses.
Energy lost to a system as a result of friction is a classic example of thermodynamic irreversibility.
Read more about this topic: Friction
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