Longevity Of Magnets.

[modeller]

Following on from honey dip question I have box of powerful permanent magnets which are 60 odd years old and appear as strong as ever.

I wonder what they will be like in another 60 odd years.

[Nibble]

As the magnets have been "magnetically" charged for 60 odd years, then unless the ambient heat in which the magnet is stored doesn't reach the temperature at which the magnet changes state from solid to liquid, then there is normally no change discernable in the magnetic charge for as long as it exists. Or, at least until the above acts upon the magnet. IMO

[pdq1]

As magnets are the source of nearly free energy its a wonder more has not been made for their use. For instance in the latest wind turbines magnets are used to keep the sails turning when the wind is not powerful enough.

[Teddio]

pdq: Are you implying that the magnets themselves are a source of energy ?

[pdq1]

Some examples Teddio

http://www.bing.com/images/search?q=magnets+in+wind+turbines&qpvt=magnets+in+wind+turbines&;FORM=IGRE

[Teddio]

The wind turbine produces electrical energy by transferring kinetic energy in the moving air to electrical energy via electromagnetic induction. There is no energy contribution from the magnets themselves, no matter how strong.