NEB Class 11 Physics: First Law, Carnot Cycle & Heat Engine Efficiency

Thermodynamics in Class 11 Physics balances quantitative calculus with conceptual thermodynamic cycles.

The 4 Stages of the Carnot Cycle

1. Isothermal expansion at temperature $T_1$ ($Q_1$ absorbed).
2. Adiabatic expansion (temperature drops from $T_1$ to $T_2$).
3. Isothermal compression at temperature $T_2$ ($Q_2$ rejected).
4. Adiabatic compression (temperature rises back to $T_1$).