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title: "A heat engine operates in a continuous cycle between a high-temperature reservoir at \\(T_H = 600 \\text{ K}\\) and a low-temperature reservoir at \\(T_C = 300 \\text{ K}\\). In each cycle, the engine absorbs \\(1200 \\text{ J}\\) of heat from the high-temperature reservoir and performs \\(400 \\text{ J}\\) of net work. Which of the following correctly compares the efficiency of this heat engine to the theoretical maximum Carnot efficiency between these two reservoirs, and provides correct reasoning?"
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url: "https://nerd-notes.com/ubq/117351/"
date_modified: "2026-08-04T06:51:54+00:00"
---

# A heat engine operates in a continuous cycle between a high-temperature reservoir at \(T_H = 600 \text{ K}\) and a low-temperature reservoir at \(T_C = 300 \text{ K}\). In each cycle, the engine absorbs \(1200 \text{ J}\) of heat from the high-temperature reservoir and performs \(400 \text{ J}\) of net work. Which of the following correctly compares the efficiency of this heat engine to the theoretical maximum Carnot efficiency between these two reservoirs, and provides correct reasoning?

A heat engine operates in a continuous cycle between a high-temperature reservoir at \(T_H = 600 \text{ K}\) and a low-temperature reservoir at \(T_C = 300 \text{ K}\). In each cycle, the engine absorbs \(1200 \text{ J}\) of heat from the high-temperature reservoir and performs \(400 \text{ J}\) of net work. Which of the following correctly compares the efficiency of this heat engine to the theoretical maximum Carnot efficiency between these two reservoirs, and provides correct reasoning?

- **A.** The efficiency of this engine is greater than the Carnot efficiency because the ratio of heat absorbed to work performed is \(3:1\).
- **B.** The efficiency of this engine is equal to the Carnot efficiency because any engine operating in a closed thermodynamic cycle has an efficiency equal to \(1 - \dfrac{T_C}{T_H}\).
- **C.** The efficiency of this engine is less than the Carnot efficiency because the net change in internal energy of the gas over one complete cycle is negative.
- **D.** The efficiency of this engine is less than the Carnot efficiency because its actual efficiency of \(33\%\) is less than the theoretical maximum efficiency of \(50\%\).

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/117351/*