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Author Topic: Dropping Magnets !!....loses their magnetivity ?? (new word ?)  (Read 8791 times)

Offline neilep

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Is this true ?

Has anyone heard of this ?..that if you drop a magnet it weakens it's magnetic strength ?

How so and why so ?


thanks

neil


 

Offline Karen W.

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I have not heard that, but should test it. I wonder if it is cumulative? You

know, every time one is dropped it becomes less magnetic or does it simply

just happen that quick and thats it? If it is true, I am curious about the

out come and progression.

Scenario.. I have my child,.. I hold her over the balcony let go she

falls to the ground cracks her skull gets a headache and bump but still is fine.

so here it is next day I repeat the drop from the balcony.. now the child has a bump a

cracked skull, a headache and slurred speech, still she

functions at less then her normal happy self..but functions she does. Again

the next day, same thing happens this time the crack widens  and she becomes

erratic and incoherent not functioning well at all, next day repeating same

drop, but this time when retrieved there are no reactions at all and she has

died..! ( I know that is radical comparison,) But is this

basically what will happen to the magnet over time as it is repeatedly dropped??? Will it

eventually stop working all together and become totally non magnetic? :)
« Last Edit: 15/10/2007 19:44:22 by Karen W. »
 

Offline Mr Andrew

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Permanent magnets are magnetic because of what are called domains, groups of atoms inside the material whose magnetic moments are all pointing in the same direction.  Their domains are all pointed in the same direction and so produce a net magnetic field.  When you drop the magnet, some domains become disoriented and no longer line up with the other ones--the net magnetic field is weaker.  Every time you do this, more and more domains flip and eventually the magnet is no longer magnetic.  I think it is possible to remagnetize permanent magnets using an external magnetic field (flip the domains back into alignment) but I'm not sure.
 

Offline sohail

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Yes, you can remagnetize permanent magnets I think; I remember doing it in Physics when I was litte! :)
 

Offline syhprum

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Yes this used to be so but modern magnets are made of much tougher stuff today and I don't think a modern one would come to much harm
 

Offline neilep

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Permanent magnets are magnetic because of what are called domains, groups of atoms inside the material whose magnetic moments are all pointing in the same direction.  Their domains are all pointed in the same direction and so produce a net magnetic field.  When you drop the magnet, some domains become disoriented and no longer line up with the other ones--the net magnetic field is weaker.  Every time you do this, more and more domains flip and eventually the magnet is no longer magnetic.  I think it is possible to remagnetize permanent magnets using an external magnetic field (flip the domains back into alignment) but I'm not sure.

fascinating stuff !..Thank you very much Mr Andrew. I heard it somewhere and you're explanation has been most helpful.
 

Offline neilep

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Yes, you can remagnetize permanent magnets I think; I remember doing it in Physics when I was litte! :)

Excellent, more confirmation...Thank you.
 

Offline neilep

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Yes this used to be so but modern magnets are made of much tougher stuff today and I don't think a modern one would come to much harm

This is great news. But would it take a long time for it to happen anyway ?....and I imagine a large number of knocks and bumps!

Thank You very much.
 

Offline Karen W.

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So the old ones did work that way but newer are stronger and will stay together so to speak better. and even the older ones can be remagnetized.
 

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