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Hello everyone.
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This is problem 49 from chapter 18.
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It tells us that the efficiency of a particular carnot engine is some number.
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It then asks if the high temperature reservoir is at a certain temperature, what is the temperature of the low temperature reservoir? so let's do this part, this is just part a.
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We'll do these one at a time here.
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So we know that the efficiency of a carnot engine is 1 minus t .c over th.
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And whenever you're dealing with carnot engines, you should keep this equation in your back pocket.
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It's very useful.
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Anytime a carno engine is mentioned, it's very likely that you're going to be using this equation.
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So using this equation, we can rearrange to find tc.
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And so we have th given in the problem, and we have the efficiency, which is also given in the problem.
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And so we can calculate this to be approximately 407 kelvin.
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So this is the answer to part a.
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Part b asks to increase the efficiency of the engine to 40 % from where we are, which is at 28%.
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Must the temperature of the low temperature reservoir be increased or decreased? explain...