Control Mass

First Law of Thermodynamics:

dE=δQδW

Second Law of Thermodynamics:

mcv(t)+δmin=mcv(t+δt)+δmout

Entropy:

Before:
Scv(t)+δminsin
After:
Scv(t+δt)+δmoutsout
Change:
dScm=[Scv(t+δt)+δmoutsout][Scv(t)+δminsin]
Final Equation:
dScvδQT+δminsinδmoutsout

Differential:

dScmδQT

Rate Equation:

dScmdtQ˙T