An electrical generating plant operates at a boiler temperature of 200°C and exhausts the unused heat into a nearby river at 20°C.What is the maximum theoretical efficiency of the plant? (0°C = 273 K)
A) 61%
B) 38%
C) 21%
D) 41%

Question

Quizplus · Accepted Answer

The maximum theoretical efficiency of the plant can be calculated using the formula: efficiency = 1 - Tcold/Thot, where Tcold is the temperature of the cold reservoir (in Kelvin) and Thot is the temperature of the hot reservoir (in Kelvin). Converting the given temperatures to Kelvin, we get:
Tcold = 20 + 273 = 293 K
Thot = 200 + 273 = 473 K
Using the formula, efficiency = 1 - 293/473 = 0.38, which is 38%. Therefore, the correct choice is B.

An Electrical Generating Plant Operates at a Boiler Temperature of 200°C