Robin van Spaandonk wrote:
. . . heat conducts very slowly compared to the timescale of a
nuclear reaction. It conducts at the speed of sound.
The speed of sound in metals is on the order of thousands of meters
/ second. If
heat conducted at that speed you would burn your fingers the instant you put
your teaspoon in your coffee.
Huh. Good point. And yet I have often read that the heat conducts at
the speed of sound. Perhaps that means something like: the first
temperature rise (vibration) in a long copper bar reaches a sensor at
the speed of sound. Not that the entire thing comes up to the same
temperature instantaneously. Maybe it reaches the other end quickly
but attenuates.
- Jed
