2
$\begingroup$

I was reading about electromagnetism and gravity and their relationship in the Einstein field equations, where I stumbled across this post: Does gravity affect magnetism, vice-versa, or do they "ignore" each other?

So my question now is does gravity affect the ability of a magnet to repel/attract other magnets? For example, if I were to set up two identical experiments, one on space and one on earth, where identical magnets were placed a distance from each other, would one experiment yield faster attraction times than the other? Putting friction forces and air resistance aside, of course. Thanks!

$\endgroup$

3 Answers 3

2
$\begingroup$

Gravity does not directly couple to electromagnetism. If it did, then we could use batteries and coils of wire or capacitors to make gravity, and generate electricity in a wire by moving it around in a gravitational field.

Energy does couple to gravity; in this sense a hot object will weigh a tiny, tiny bit more than it did when it was cold, a compressed spring will weigh a tiny, tiny bit more than it did when it was relaxed, and so on. This means a strongly-magnetized piece of samarium-cobalt magnet material will also weigh a tiny, tiny bit more than it did before it was magnetized.

But all these effects are far too small to measure.

$\endgroup$
1
$\begingroup$

Permeability of air is larger than that of vacuum. With a ratio of 1.00000037. So force in your experiment on earth will be this much stronger just because of air as a medium.

If you would ask an outside observer, he would also notice the time dilation due to Earth's gravitation well, it will make exprtiment run a bit slower, 1-(7e-10). Same effect for the Sun and Milky Way, but im not sure how to calculate it.

You could also account for Earth's motion, it would make the experiment a bit slower, by 1-(1e-12) for spinning, 1-(5e-9) for orbital motion around the sun and 1-(3e-7) for its motion around the Milky Way

If your magnets will be really, really strong, you would create matter, that would create gravitational force in return. You probably wont be able to get such magnetic field.

But you dont even need that strong of a field in order to affect gravity. Since energy and matter are not that different, adding more energy into your magnetic field will already create more gravitational force. A bit. A Hiroshima's nuke worth of energy would add gravitational force the same as would 7 grams. So if you can measure gravitational force of your energy, you either have very good measuring tools, or you should be really really careful.

1-(4e-3) means "1 minus 4 with 3 leading zeros: 1-0.004, or 0.996". Lazy way to write long numbers. Scientists use it, but we can use it too. 7e4 would mean 7 with 4 zeros after it, 70000.

If you wanted to make a flying skateboard with fridge magnets, then no, it wont work. Even if YouTube shows otherwise.

$\endgroup$
0
$\begingroup$

This is a good question, according to me magnet will attract or repel more efficiently and from more distance because on earth they have to first overcome the gravitational force and then they will attract or repel each other but as in space there is no gravity and air resistance too. So they will work more efficiently.

$\endgroup$
1
  • 1
    $\begingroup$ Your answer could be improved with additional supporting information. Please edit to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers in the help center. $\endgroup$
    – Community Bot
    Dec 6, 2023 at 12:37

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.