Carnot's engine is reversible, so if run backwards it acts as:

  1. a generator of energy
  2. a refrigerator (or heat pump)
  3. a stronger engine
  4. a thermometer
Answer

B) a refrigerator (or heat pump)

Heat is pumped from cold to hot. SLO P-11-C-16 · Understanding

Physics MCQ · More Heat Engines, Second Law and Entropy MCQs · Practise