The turbine in a steam power plant takes steam from a boiler at 427 °C and exhausts into a low temperature reservoir at 77 °C. What is the maximum possible efficiency?
Correct answer: A. 50%
- A. 50%
- B. 40%
- C. 60%
- D. 70%
Explanation
To find the maximum possible efficiency of the steam turbine, we use the Carnot efficiency formula: η = (T1 - T2) / T1, where T1 and T2 are the absolute temperatures of the heat source and sink, respectively. Convert the given temperatures from Celsius to Kelvin: T1 = 427°C + 273 = 700K, T2 = 77°C + 273 = 350K. Substituting these values into the formula gives η = (700K - 350K) / 700K = 0.5, or 50%. This is why option A is correct. Options B, C, and D are incorrect because they do not match the calculated efficiency using the Carnot formula.
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