Why does magnetic force tend to increase magnetic energy?

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SUMMARY

The discussion centers on the relationship between magnetic force and magnetic energy, specifically addressing why magnetic forces can lead to an increase in magnetic energy. Two key scenarios are identified: first, when a magnet is brought closer to a metal, resulting in energy loss as the system compensates for the decreasing magnetic path; second, when energy is added to the system by increasing the current in an electromagnet, which enhances the magnetic field strength. The conversation highlights the importance of air gaps in magnetic devices, particularly in inductors designed for higher energy storage, where the majority of energy resides in the air gap.

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  • Understanding of magnetic force and energy principles
  • Familiarity with electromagnetism concepts
  • Knowledge of inductors and their design
  • Basic principles of energy conservation in physical systems
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  • Study the effects of air gaps in magnetic circuits
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BrunoIdeas
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Hello. So: Why does magnetic force tend to increase magnetic energy?
1) Usually, forces go in the direction of energy minimums. Why in this case is the opposite?
2) What does it imply?

What is that makes magnetism particular in some senses, for example this, for example its force function form?

Thanks to everyone.
 
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It doesn't. Perhaps you could explain what it is that is leading you to think otherwise.
 
I could see two instances in which you would experience an increase in force:

1) When you have a fixed source, but you are decreasing the length of the magnetic path (i.e. by bring a magnet closer to metal)
2) When you have a fixed magnetic path (all metals parts stay in place), but you increase the field strength through adding energy to the system (i.e. increasing the current through an electromagnet).

In case 1, you are actually losing energy in the system as you bring the magnet and metal closer together. The system is giving up energy to whatever is holding the two pieces. That is, there is a distance and force which equates to energy. Likewise, when you pull the magnet from the metal, you give up energy in your efforts, and the field gains energy.

In case 2, yes, you are putting more energy into the field through increase of the current.

In a magnetic device containing a source of magnetization, a ferromagnetic material, and an air gap, the majority of the energy is typically in the air gap. Thus engineers designing inductors typically have larger air gaps in those which are designed for higher energy storage ( E=I^2 L).
 

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