- A
- B
- C
- D
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Correct answer: EXACT CORRECT RESULT: $$\LEFT(\LN\FRAC{473}{373},\,\LN\FRAC{473}{373}\RIGHT).$$, IF FORCED TO CHOOSE FROM THE GIVEN OPTIONS, THE INTENDED OPTION IS **D** ONLY BECAUSE ENTROPY CHANGE MUST BE SAME IN BOTH CASES, BUT THE VALUE $\LN 2$ IS INCORRECT.
- Given data
- Heat capacity of body: (constant)
- Initial temperature:
- Final temperature:
For entropy change, we must use absolute temperature:
- Entropy change of the body
Entropy is a state function, so it depends only on the initial and final states, not on the path or number of reservoirs.
For a body of constant heat capacity ,
Substituting :
This is the entropy change in both cases.
- Check the options
Numerically,
so
Now compare with listed forms:
None of these equals .
So the correct physical result is:
- Interpretation with respect to options
Since entropy change of the body is same in both processes, the pattern must be . Among the given options, only D has equal values in both cases.
However, its value is not numerically correct. The exact correct value should be
Thus the option structure suggests D, but the value stated is incorrect.
- Final conclusion
- Derived entropy changes:
- Among options, the only matching qualitative choice is D.
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