Classical Thermodynamics

Classical thermodynamics is the study of heat, energy, and their relationship to work. It describes how thermal energy is converted to and from other forms of energy and how it affects matter.

Fundamental Concepts

  • Temperature and Heat
  • Internal Energy
  • Work and Heat Transfer
  • Entropy
  • Thermodynamic Systems

Laws of Thermodynamics

Zeroth Law

If two systems are in thermal equilibrium with a third system, they are in thermal equilibrium with each other.

First Law

Energy cannot be created or destroyed, only converted from one form to another.

ΔU=QW\Delta U = Q - W
Learn more about the First Law →

Second Law

The entropy of an isolated system always increases.

ΔS0\Delta S \geq 0
Learn more about the Second Law →

Third Law

As a system approaches absolute zero temperature, all processes cease and the entropy approaches a minimum value.

Heat Transfer Mechanisms

  • Conduction - Transfer through direct contact
  • Convection - Transfer through fluid motion
  • Radiation - Transfer through electromagnetic waves
Learn more about Heat Transfer →

Applications

  • Heat engines and refrigeration
  • Phase transitions
  • Chemical reactions
  • Power generation
  • Climate science