How Does Forcing Magnets Together Affect Spatial Energy and Distortion?

AI Thread Summary
Forcing like poles of magnets together compresses the magnetic field, storing additional energy proportional to the work done. The space between the magnets is affected by this compression, but remains largely unchanged when the magnets are separated slightly. The relationship between the force and distance is not linear, often following an inverse law depending on the magnets' shape and orientation. While the space itself is mostly unaffected, it serves as a medium for observing electromagnetic fields. Measuring the distortion of linear space due to magnetic forces remains a complex challenge.
ChrisWhewell
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I'm curious to know how the space between two magnets arranged so their like poles are forced to be nearer to one another is distorted. Is the energy in the space between such poles at a higher state than the surroundings, in an amount proportional to the force exerted in bringing the magnets poles together, or is the space un-affected ?

Similarly, is the space between two magnets that are stuck to one another affected when they are withdrawn, out to say 1 mm ?
 
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Your intuition is right on this. To bring two magnets together with like poles facing each other, you have to push them together, doing work. This additional energy is stored in the magnetic field. In terms of lines of force, the B field is being compressed. To bring magnets together with unlike poles facing each other, the magnets exert an inward force on your hands, doing work on you, and the resulting B field has less energy.
 
Bill_K said:
Your intuition is right on this. To bring two magnets together with like poles facing each other, you have to push them together, doing work. This additional energy is stored in the magnetic field. In terms of lines of force, the B field is being compressed. To bring magnets together with unlike poles facing each other, the magnets exert an inward force on your hands, doing work on you, and the resulting B field has less energy.

hooke's law F=kx, can integrate to calculate the work from given displacement limits, but I'm wondering about what, if anything, happens to the space between the magnets.
 
Hooke's law applies in a linear regime. The force between two magnets does not have a linear relationship[ with distance. It will be some sort of inverse law, depending on the actual shape and orientation of the magnets. Between the poles of two very long bar magnets, you will get an approximate inverse square law. Not Hooke's Law trerritory.

The space in between is sort of 'just there' and it's somewhere the fields can be observed in. For EM waves and fields, empty space is linear so the fields will just 'add together'. The mass of your magnets would be doing it's little bit of space distortion to account for the minuscule gravitational force between them.
 
sophiecentaur said:
...empty space is linear ...

sophiecentaur said:
... The mass of your magnets would be doing it's little bit of space distortion...

How can the distortion of linear space be measured ?
 
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