The Carnot cycleï¿½-ï¿½The WikiPremed MCAT Course

Introduction
Video Course
Science Topics
Diagnostic Tests
Physics Flashcards
Orgo Mechanisms
Question Server
Physiology Puzzles
~~Writing Section~~
Verbal Reasoning
Web Links
WikiPremed Bundle

Contact Us

Integrated Sequence	Physics	Chemistry	Organic	Biology

The Second Law of Thermodynamics and Heat Engines

Thermodynamic cycles

The Thermal Efficiency of a Heat Engine

Heat Pumps and Coefficient of Performance

The Carnot cycle

Entropy

Web Resources

HyperPhysicsï¿½-ï¿½Carnot Cycle

Special points of emphasis

The First Law of Thermodynamics

The Second Law of Thermodynamics and Heat Engines

To understand the significance of the Carnot cycle, you need to have both the First and Second Laws of Thermodynamics in your analytical toolkit. Each stage of the Carnot cycle should be assessed in terms of both laws.

The First Law of Thermodynamics allows us to describe each step in terms of heat flow, work performed, and internal energy change. The Second Law enables us to discuss how the changes in entropy in the system and surroundings are balancing out at every stage. Every stage of the Carnot cycle is microscopically reversible, and the entropy of the universe does not increase.

However, heat still must be expelled at the cold sink, even though entropy is not increasing. Otherwise, entropy in the universe would actually decrease. By being reversible, the Carnot cycle finds the limit of heat that can be turned into work without decreaseing the entropy of the universe. In this sense, the Carnot cycle represents the ideal (most efficient) thermodynamic cycle possible. Compared to the Carnot cycle, all real cycles would result in even more heat being lost to the cold sink.

The WikiPremed MCAT Course is a free comprehensive course in the undergraduate level general sciences. Undergraduate level physics, chemistry, organic chemistry and biology are presented by this course as a unified whole within a spiraling curriculum.

Please read our policies on privacy and shipping & returns.ï¿½ï¿½Contact Us.
MCAT is a registered trademark of the Association of American Medical Colleges, which does not endorse the WikiPremed Course.

The work of WikiPremed is published under a Creative Commons Attribution Share Alike 3.0 License. There are elements of work here, such as a subset of the images in the archive from WikiPedia, that originated as GNU General Public License works, so take care to follow the unique stipulations of that license in printed reproductions. You can use the resources here for commercial or non-commercial purposes, but please give attribution and a link to the production credits and edit history of the resource. For the works here which began as my individual work, please attribute "John Wetzel, an author at wikipremed.com".