Is a Velocity Dependent Force Always Non-conservative?

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SUMMARY

A velocity-dependent force is generally non-conservative, as it can perform different amounts of work along the same path depending on the velocity of the object. The discussion highlights the magnetic force as an exception, where it is often considered conservative despite its velocity dependence, due to the work done being zero on a charged particle. To mathematically demonstrate that a velocity-dependent force is non-conservative, one must analyze the curl of the force vector field, which is not guaranteed to be zero. This distinction is crucial for understanding the nature of various forces in physics.

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Gaudium
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Hi, I understand that a conservative force cannot depend on velocity, because by changing velocity we can do different work on the same path. But how can I show this mathematically, for a general force depending on velocity? Is the curl always zero for such a force?

Thank you?

Nese
 
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Are you sure about that? What about the force a magnetic field exerts on a moving charge?
 
Yeah, you are right. As far as I know some people see the magnetic force as a conservative force although it depends on velocity, because the work done by it on a particle is always zero. I do not know any other force with this property. Maybe I have to reformulate the question as how do we show that a velocity dependent force is not conservative, which has nonzer work on the particle?
 

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