Using magnetic energy and causing degradation of the field

AI Thread Summary
The discussion revolves around the concept of utilizing magnetic energy without affecting the magnet itself. A participant questions whether this method would lead to faster degradation of the magnetic field. Another contributor clarifies that inducing voltage in a coil by moving it near a magnet does not physically alter the magnet, addressing a common misconception about magnetic fields. The idea that magnetic fields store energy to be "used up" is also challenged. Overall, the conversation highlights the complexities of magnetic energy usage and its implications on field integrity.
quantumfoam
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Hi guys! I was wondering something about magnetic energy and well, I stumbled on to this. If there was a way to use a magnetic field's energy without influencing the actual magnet, would the degradation of the field increase at a faster rate?
 
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quantumfoam said:
Hi guys! I was wondering something about magnetic energy and well, I stumbled on to this. If there was a way to use a magnetic field's energy without influencing the actual magnet, would the degradation of the field increase at a faster rate?

Could you maybe give an example to illustrate what you are asking? The question is not very clear yet.

If you have a permanent bar magnet mounted to the edge of a desk, and you wave a coil of wire in front of the end of it, you will induce a voltage in the coil. That doesn't physically alter the bar magnet...
 
This seems to be another of those misunderstandings that people have ... that a magnetic field is stored energy that you can use up

Dave
 

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