# Magnet question

Discussion in 'Physics' started by amilton542, May 6, 2011.

1. ### amilton542 Thread Starter Active Member

Nov 13, 2010
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If a magnet was left in space till the end of time would it still be as strong as it originally was?

2. ### BillO Distinguished Member

Nov 24, 2008
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The end of time is a long way off.

If it was at absolute zero, it might just.

3. ### amilton542 Thread Starter Active Member

Nov 13, 2010
496
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Then there must be a demagnetizing force acting on the magnet

4. ### BillO Distinguished Member

Nov 24, 2008
993
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Well, there will be varying magnetic fields out there, regardless of how tiny, and in the real universe there will be some temperature. Given forever, they are likely to get the job done.

BTW, I meant if it were at absolute zero, temperature wise, the magnetic field might just last forever.

5. ### t_n_k AAC Fanatic!

Mar 6, 2009
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Cosmic radiation would probably have an effect.

Being the end of time - who (or whom) will be around to check one way or the other? If so will they really be all that interested. If they were still around (and interested) they probably already knew the outcome in advance.

It's an interesting philosophical question.

6. ### magnet18 Senior Member

Dec 22, 2010
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If a man does something and no woman is around to see it, did he still do it wrong?

7. ### BillO Distinguished Member

Nov 24, 2008
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Of course!

I just asked my wife and she verified.

8. ### Wendy Moderator

Mar 24, 2008
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Always nice to have expert advice handy.

9. ### amilton542 Thread Starter Active Member

Nov 13, 2010
496
64
If the magnet was in a sterile vacuum that is absent from the dangers of space there must always be something that will demagnetize the magnet because nothing lasts forever.

I think any civilization at that time scraping an existence around a red dwarf would have more important things to worry about, o well

10. ### t_n_k AAC Fanatic!

Mar 6, 2009
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If it were possible to isolate the magnet from all external influences then there would be nothing to demagnetize it.

If nothing lasts forever does the magnet itself physically vanish before it demagnetizes?

11. ### amilton542 Thread Starter Active Member

Nov 13, 2010
496
64
I didn't think about that one. YES the magnet would vanish before it demagnetizes

12. ### magnet18 Senior Member

Dec 22, 2010
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Yet if it vanishes energy must be created, so the vacuum is no longer perfect and sterile.

13. ### Kermit2 AAC Fanatic!

Feb 5, 2010
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wouldn't that depend on ones definition of 'vanished'?

14. ### t_n_k AAC Fanatic!

Mar 6, 2009
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Then there's always the First Law of Thermodynamics to contend with.

or another issue regarding observers ...

"If a tree falls in a forest and no one is around to hear it, does it make a sound?"

15. ### Markd77 Senior Member

Sep 7, 2009
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I think the magnets own magnetism is a demagnetising force.

16. ### Wendy Moderator

Mar 24, 2008
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There are two forces that demagnetizes a magnet, heat and mechanical shock. If it were cold and static I think it would last quite a while. Probably longer than humans.

Have I missed something?

17. ### t_n_k AAC Fanatic!

Mar 6, 2009
5,448
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No, the universe is still here - I think....???

Perhaps we have wandered into metaphysics.