xkcd #3115: Unsolved Physics Problems
Title text:
‘Tin pest’ makes more sense to me. Tin just doesn’t want to be locked down in a shape like that. I get it. But why would any metal want to grow hair??
Transcript:
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Source: https://xkcd.com/3115/
Metals are crystals ao why wouldn’t they grow hairs? Probably just stray electrons and alignment issues lining up. Crystals do things, what’s the big deal?
Everything we know about the way metal crystals grow is against they growing up hairs.
I’m not sold on that. I am probably engineer over-generalizing rn, but I can totally see hairs growing as a result of directional growth rate differences and localized fluidity changes caused by the presence of defects in polycrystalline zinc exposed to an electron current.
There could also be a resonance phenomenon caused by waves in the current moving around imperfections the metal.
Maybe the metal atoms undergoing electron drift are guided by electric fields through the air to areas of differing voltage, a self-fulfilling short circuit.
I’m going to guess the challenge lies in isolating and observing these effects to figure out precisely what is going on.
Just to point, but the hairs appear wherever you put some electrical current on the metal or not.