Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Ronaldous on 18/08/2017 23:52:34
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What if I take a powerful magnet and grind it into fine particles placing the contents in an empty globe then place it in outer space where it is set in motion and spinning as is the planet earth. Will it have a N and S pole? Will it attract matter as does Earth? Have I replicated gravity? Is this what gravity is? Is gravity the combined forces of all the atoms on our planet working in unison creating gravity as we know it? I'm certain their magnetetic forces of attraction far exceed the outer layer of electrons spinning around the nucleus... Your thoughts please?
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I take a powerful magnet and grind it into fine particles
The severe mechanical vibration and heating of a grinder is likely to eliminate all magnetism from a powerful magnet. A grinder will heat the magnet above its Curie temperature (https://en.wikipedia.org/wiki/Curie_temperature), and it will lose its magnetism.
fine particles placing the contents in an empty globe...Will it have a N and S pole?
No.
Let's say you have a fine powder, in which you have managed to retain the magnetism in each particle.
Like putting two bar magnets near each other, the particles will flip around and cancel the magnetic field of the adjacent particles, leaving no overall magnetic field.
Will it attract matter as does Earth?
No.
If you left the original powerful magnet intact, with its external magnetic field, it would attract iron and cobalt strongly (ferromagnetic materials), but the same mass of other materials like human bodies will feel almost no attraction at all (paramagnetic materials) a very slight repulsion (diamagnetic materials) - correction.
This is quite unlike gravity, where a 70kg human feels the same attraction as 70kg of iron.
When spacecraft travel into space, the gravitational force decreases as an "inverse square law": Double the distance, and the force reduces to one quarter.
This is quite unlike magnetism: once you get far enough away, magnetic fields decrease like an "inverse cube law": Double the distance, and the force reduces to one eighth.
See: https://en.wikipedia.org/wiki/Magnetism
Is gravity the combined forces of all the atoms on our planet working in unison creating gravity as we know it?
Yes.
The mass of all Earth's atoms attracts the mass of all your atoms.
However, the magnetic field of all Earth's atoms is very weak, at around 20-60μTesla (about 20,000 times weaker than the typical magnetic field inside an MRI machine). And the magnetic field of a human body is almost nil. So even a 1.5 Tesla MRI magnet has minimal attraction for the atoms of your body.
I'm certain their magnetic forces of attraction far exceed the outer layer of electrons spinning around the nucleus
It takes ultraviolet light or an electric spark to rip electrons away from their parent atom*.
The magnetic field inside an MRI machine is not strong enough to rip electrons off their parent atoms.
Summary
Magnetism is a totally different force than gravity; magnetism is part of the electromagnetic force.
- So you can't simulate gravity using magnets.
- The closest you come is in science fiction movies, where they use magnetic boots to anchor astronauts to an iron spacecraft.
*for electrical conductors like copper, an electron doesn't really have a "parent atom".
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but the same mass of other materials like human bodies will feel almost no attraction at all (paramagnetic materials).
Actually, it's even more different that that.
The human body is repelled by a magnetic field. It is diamagnetic.
So, you can- in some circumstances use a powerful magnetic field as a sort of "anti gravity".
https://en.wikipedia.org/wiki/Magnetic_levitation
Gravity never does that sort of thing because (at least, as far as we know) gravitational forces are always attractive.
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That’s a great answer, Evan. The only point with which I would take issue is:
“Will it attract matter as does Earth?”
“No.”
Surely, it would attract matter, but that would be by gravity, not magnetism. Of course, we all knew that was what you meant, but we pedantic pests can’t always resist chipping in. :)