I understand the basics of magnetism; charge, fields, etc, but I don’t understand how a magnetic field can apply force seemingly forever.
For example, if I bring a magnet close to another magnet, that other magnet will eventually be drawn to the magnet in my hand, causing it to move. That kinetic energy “is caused by the magnetic attraction” but how?
If I keep my hand between two magnets, they will squeeze against my hand for seemingly forever. If I were to squeeze my own hand, I’ll get tired eventually from the exertion, but magnets don’t “get tired.” Are magnets somehow infinite energy machines? I’d assume they aren’t, but where is this energy coming from and why does it seem endless?
Edit: yes I understand the difference between “force” and “energy,” defining those terms doesn’t actually answer my question!
In: Physics
Not directly answering the question but many people get force and energy confused.
A force can exist forever and requires nothing to maintain. Energy only comes in when the force is able to do/move something. A magnet can apply a magnetic force and hold on to your hand from now until eternity if you ignore the physical materials degrading. You holding up an object is not quite the same.
Your muscles are constantly moving little strands by tightening and releasing them. This is why (in part) it takes energy and you get tired. Some creatures are able to move their body such that it “latches” into place and no longer requires any energy or effort to hold in position.
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