- #1

muzialis

- 166

- 1

I have a question on the dissipation and entropy.

Let us consider a newtonian dampener with viscosity coefficient η, pulled at a fixed rate e', immersed in an infinite bath at temperature T.

The mechanical work input in time dt is then dW = ηe'*e'dt, and is all dissipated into heat.

The bath will see an increase of its entropy of -dW/T.

And the dampener? Some might argue that it will exchange heat with the bath, but its entropy gain cannot be opposite and equal the entropy gain of the bath, as the second law prescribes the entropy for the overall dissipative sistem has to increase.

So how do I compute the total change in entropy? Where is the "additional" entropy coming from, to satisfy the second law?

I am so puzzled, hop somebody can relieve me!

Thanks