|MadSci Network: Physics|
Sarah, you ask:
"I thought a quarter would be attracted to a magnet, but tried it and it wasn't. Could you explain this to me??"
Only certain kinds of metal are attracted to magnets (common examples are iron, steel, nickel, and cobalt). US quarters don't have enough of any of these kinds of metals to be attracted to a magnet.
In fact, very few coins are attracted to a magnet. Modern nickels don't have enough (if any) nickel in them to be attracted to a magnet.
I have lots of strange coins in my desk drawer that I have brought back from many trips. I found only one that was attracted to a magnet, and it is really a token (for what and where I don't remember).
The only real coin I can think of that would be attracted to a magnet would be one of the "steel pennies" that the US made during the 2nd World War when copper was in short supply. And I haven't seen one of those for a long time.
One nice on-line source on magnets is the Canadian Science and Technology Museum at www.sciencetech.technomuses.ca
Medical College of Wisconsin
[note added by MadSci Admin: Search for information about paramagnetism and diamagnetism to learn why some metals are attracted and others are not!]
Try the links in the MadSci Library for more information on Physics.