Can Magnets Actually Store Energy?

AI Thread Summary
Magnets can store energy in their magnetic fields, quantified by the formula energy density = 1/2 B^2/μ, where B is the magnetic field strength and μ is the permeability. This energy is significant, especially in applications like electrical coils, which are essential for transforming electric energy in power grids. The energy stored in magnetic fields can be substantial, as demonstrated by superconducting coils at facilities like the LHC, which can hold several gigajoules. Understanding magnetic energy is crucial for various technologies, highlighting the importance of conservation of energy in these systems. Overall, the energy in magnetic fields is both real and useful in practical applications.
Hypo
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Hallo everyone!

I'd like more about the energy in the magnetic fields of a magnet is there major amounts of energy?

What is the formula?(explain units or name of the formula please so I can learn more about it)

I never thought that magnets would have Energy :bugeye: Only thought of its forces that's all.

Can anyone give out an explanation of that energy and is it in anyway useful?

Thanks!
 
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the energy density of a magnetic field is 1/2 B^2/\mu
So if you have a region with a magnetic field, you integrate that over the region to find the total energy of the magnetic field.


think of it like a hose - pushing the ends of opposing hoses together is hard because the water is pushing them apart.

The reason there is energy in the magnetic field is the same as the hose - you need energy to have the water flowing.

But these analogies only start to make sense of it, there is no "flowing water" in a magnetic field, unless you're a fan of the old ether theory. Just think of it as a "thing" and whenever there is a "thing", no matter what it does, energy is needed to create it and the energy is stored in it until it is destroyed. Conservation of energy always applies.
 
Energy of magnetic fields are important in coils - in fact, this is the reason why coils are built at all.
As an example, the electricity grid relys on coils to transform the electric energy it between different voltages.

The superconducting coils at the LHC can store several gigajoules, this is the same order of magnitude as the kinetic energy of a flying Boeing 747 and enough to supply a small house with electric energy for a significant fraction of a year.
 
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