Tuesday, August 3, 2010


The relation of the viscous friction coefficient and the diffusion coefficient to thermal energy is a very cool example of gaining deeper insights by playing around with formulae. I would like to know how it is that the energy is transferred from the moving particle to the fluid. My guess is that the random movements of the particle and the random movements of the fluid are somehow coupled and have the same vibrational modes. If correct this makes sense to me. However I wonder how this causes a slow down in the particle i.e. how is kinetic energy of a single particle degraded into heat?

1 comment:

  1. Again, I understand kinetic energy being degraded into heat to be due to the motion of that particle becoming 'out-of-sync' with the motions of the other particles in the system. After all, heat is just the average kinetic energy of particles in a system, but the particles are moving in a non-unified direction.