Physics 110 Lecture 4 Entropy and the Second Law
نویسنده
چکیده
• The entropy is a state function: S = S(state). Furthermore, it is additive; S12 = S1 + S2 for a system with subsystems 1 and 2. • Entropy is unchanged in a reversible state change. That is, S(f) = S(i) and so ∆S = 0. For a reversible state change, entropy increases: S(f) > S(i), and so ∆S > 0. In all cases, ∆S ≥ 0. • When heat is added to a system, then the entropy changes by an amount proportional to the heat added:
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