I should know this, I really should.
12-gauge copper wire is rated for around 20 amps or so if it's buried in the wall of a house -- but how much current would you need to reliably melt a length of it if it's in free air? How about vaporize?In case you're wondering I'm working on a heavy-handed example of how _nothing_ in the real world is truly linear. The example I'm using is a copper wire that'll carry 20A for centuries without trouble, yet will melt (or vaporize) given a high enough overload.
Thanks.