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Q & A: hope for the future

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Most recent answer: 11/06/2009
Q:
my son and i are having a disscussion on gravity and magentism, which you didnt explain well enough on previous ones. I know they are both different forces, but my son doesnt belive me when i say you have to have magnetism to have gravity. Everything in our universe is magnetic in one way or another. so what is the cause for the other? Does gravity cause it or vice versa( i.E. our solar system as model)? But he is being told that our magnetic sphere is weaker than a common u magnet, i hardly think that is true since our sphere is overlapping all natural and artifical. So he thinks gravity has nothing to do with magnetism, but i keep saying that it is magnetism is the cuase of gravity( solar system to galatic)
- greg helton (age 39)
bellevue, washginton,usa
A:
That's a sharp kid. So far as I can tell from what you write, everything he says is correct.

Any form of energy, including magnetic field energy, can be a source of gravity. However, on earth magnetism is a completely negligible source. The rest energies (masses) of particles account for essentially all of our gravity. During the occasional times when the earth's magnetic field temporarily collapses, nothing noticeable happens to gravity.

It's true that the earth's magnetic field has less than 1 Gauss strength near the surface. A toy magnet can have 1000 times that field strength. However, the earth's field is important because it extends far enough out to help steer some incoming charged particles away from us, protecting us from that radiation.

I'm not sure I followed the meaning of some of your other statements.

Mike W.

(published on 11/06/2009)

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