What Defines a Conservative Force?

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A conservative force is defined by its compliance with the work-energy theorem, where the work done equals the change in mechanical energy. It is characterized by path independence, meaning the work done does not depend on the path taken, and is zero for closed paths. Additionally, conservative forces can be represented as the negative gradient of a potential field, indicating that their curl is zero. Examples of conservative forces include gravitational force, static friction, and elastic forces. Understanding these properties is essential for analyzing mechanical systems.
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Definition/Summary

A force is conservative (the following definitions are all equivalent):

if it complies with the work-energy theorem: work done equals change in mechanical energy

if the work done is path-independent

if the work done on a closed path is zero: \oint_C \mathbf{F} \cdot d\mathbf{s} =0

if the overall gain or loss of mechanical energy is path-independent

if the overall gain or loss of mechanical energy on a closed path is zero

if the force is a field with a potential (in which case it can be written as minus the gradient of the potential: \mathbf{F}\ =\ -\mathbf{\nabla}\Phi, and so \mathbf{\nabla}\times\mathbf{F}\ =\ \mathbf{\nabla}\times \mathbf{\nabla}\Phi\ =\ 0)

if the force is a field whose curl is zero: \mathbf{\nabla}\times\mathbf{F}\ =\ 0

Equations

\oint_C \vec F d \vec s =0

Extended explanation

A conservative force is a force such that \oint_C \vec F d \vec s =0.
Examples of conservative forces : Gravitational force, static friction force and elastic forces.

* This entry is from our old Library feature. If you know who wrote it, please let us know so we can attribute a writer. Thanks!
 
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Thanks for the overview on conservative forces!
 
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