After coming across a lovely slow motion image of a tungsten filament
heating up (link below), I was quick to explain it in a way which I now
believe was silly (thanks to a couple of readers who may well be on this
list), and I'm looking for your input.
As the filament heats up, it begins to vibrate in a gentle but
observable way, and I'm wondering how best to explain the vibrations.
(My initial assumption of thermal excitation of the constituent atoms
appears to be wrong for more than one reason, but I'd be happy to hear a
thorough critique of it here.)