How is Energy Stored in a Magnetic Field?

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Energy is stored in a magnetic field similarly to how it is in gravitational or electric fields, requiring work to create the field. The energy stored in a magnetic field can be quantified using the formula U = (1/2)∫H·B dv, where H is the magnetic field strength and B is the magnetic flux density. This energy represents the work expended to establish the magnetic field. In practical applications, such as inductors, this stored energy can be utilized when the magnetic field collapses, releasing energy back into the circuit. Understanding this process is essential for effectively harnessing energy in electromagnetic systems.
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i know how can energy be stored in an object in a gravitational or electric field simply by working on the charge or mass agianst the respective field but how can energy be stored in a megnatic field i mean how would that be explained hypothatically ?
 
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The fields that you mentioned are a form of stored energy, that is, it takes energy to create a gravitational or electric field in the first place. The same is true for a magnetic field. The energy stored in a magnetic field is

U=\frac{1}{2}\int\vec{H}\cdot\vec{B}dv

To drive home the point that the stored energy is the same as the work expended in creating the field, you'll often see this quantity called W (work) instead of U (energy).
 
marcusl said:
The fields that you mentioned are a form of stored energy, that is, it takes energy to create a gravitational or electric field in the first place. The same is true for a magnetic field. The energy stored in a magnetic field is

U=\frac{1}{2}\int\vec{H}\cdot\vec{B}dv

To drive home the point that the stored energy is the same as the work expended in creating the field, you'll often see this quantity called W (work) instead of U (energy).

so basically the work done to establish the megnatic field is stored in the inductor right but how is that energy utilized ??
 
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