College Physics I – Introduction

study guides for every class

that actually explain what's on your next test

Entropy

from class:

College Physics I – Introduction

Definition

Entropy is a measure of the disorder or randomness in a system. It also quantifies the unavailability of a system's energy to do work.

congrats on reading the definition of entropy. now let's actually learn it.

ok, let's learn stuff

5 Must Know Facts For Your Next Test

  1. Entropy always increases in an isolated system according to the Second Law of Thermodynamics.
  2. The change in entropy ($\Delta S$) can be calculated using $\Delta S = \frac{Q_{rev}}{T}$, where $Q_{rev}$ is the reversible heat transfer and $T$ is the temperature.
  3. In any real process, total entropy (system + surroundings) always increases.
  4. Entropy can be seen as a measure of energy dispersal within a system.
  5. At absolute zero temperature (0 K), a perfect crystal has zero entropy according to the Third Law of Thermodynamics.

Review Questions

  • What does an increase in entropy indicate about the disorder in a system?
  • How is the change in entropy ($\Delta S$) calculated for a reversible process?
  • Explain why total entropy always increases in real processes.

"Entropy" also found in:

Subjects (98)

© 2024 Fiveable Inc. All rights reserved.
AP® and SAT® are trademarks registered by the College Board, which is not affiliated with, and does not endorse this website.
Glossary
Guides