Answer: 2.
- A 1
- B 2
- C 3
- D 0.5
Correct answer: B. 2
Explanation: COP = T<sub>cold</sub>/(T<sub>hot</sub> - T<sub>cold</sub>) = 200/(300-200) = 200/100 = 2.
The Carnot cycle alternates two isothermal steps (heat absorbed at TH, released at TC) with two adiabatic steps (no heat exchange); the enclosed loop area equals the net work output, and η = 1−TC/TH is the maximum possible efficiency between those two temperatures.
Concept context
Laws of thermodynamics, heat engines, entropy, and gas processes.