MOL-009 · Thermodynamics Sample material

The second law of thermodynamics. The Carnot cycle

The second law of thermodynamics and its statements, reversible and irreversible processes, conversion of heat into work, heat engines and refrigerators, the Carnot cycle and theorem, entropy and the statistical meaning of the second law.

Estimated time: 3 h 4 activities

Learning objective

Distinguish reversible and irreversible processes.
Know the Clausius and Kelvin–Planck statements of the second law and understand their equivalence.
Learn the operating principle and performance measures of a heat engine, a refrigerator and a heat pump.
Derive the efficiency of the Carnot cycle and understand entropy and its statistical meaning.

Expected outcomes

Calculates the efficiency of a heat engine using $\eta = A/Q_1 = 1 - Q_2/Q_1$.
Applies $\eta = 1 - T_2/T_1$ for the Carnot cycle and compares real engine efficiencies with it.
Finds the coefficients of performance of a refrigerator and a heat pump.
Calculates entropy changes in simple processes and explains the meaning of $S = k\ln W$.

Interactive modelThe Carnot cycle

Activities

Lecture
Lecture · 1 h 20 min · required
Problem solving on the topics "Heat engines and the Carnot cycle" and "Efficiency of heat engines"
Practice · 1 h 20 min · required
Heat engines
Self-study · 6 h · optional
Final test
Test · 20 min · required · pass ≥ 70%

Completion conditions

  • Lecture
  • Problem solving on the topics "Heat engines and the Carnot cycle" and "Efficiency of heat engines"
  • Final test — at least 70%