High School Physics Competition: Change in Entropy

AI Thread Summary
In a physics competition, a question regarding the change in entropy when 1.25 x 10^3 J of heat is added to a system at a constant temperature of 75.0°C was discussed. The calculated change in entropy was found to be approximately 3.59 J/K. Confusion arose between two answer choices, with one option labeled with a hashtag, which was clarified to indicate a negative value. Ultimately, it was confirmed that the change in entropy is positive, making the correct answer +3.59 J/K. The hashtag was identified as a potential misprint, leading to the conclusion that answer c) is the correct choice.
ReneG
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During a physics competition, I came across this question.
What is the change in entropy of the system when 1.25 " 103 J of heat is added to the system that is maintained at a constant 75.0 C?

My work was
\begin{align*}\Delta S &= \frac{Q}{T} \\ \Delta S &= \frac{1.25 \times 10^3 \, \mathrm{J}}{348 \, \mathrm{K}} \\ \Delta S &= 3.59 \,\,\mathrm{\left( J/K\right )} \end{align*}

but I was stuck in between two answer choices

c) + 3.59 J/K
d) # 3.59 J/K

I had no idea what the hashtag meant, so I skipped it. Can someone clear this up for me?
 
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Honestly I have no idea, but certainly the change in entropy is positive, so answer c) is correct. Maybe it's a misprint?
 
I guess what dipole said it's right 'cause it sometimes happens
 
Last edited:
For anyone who was wondering, the hashtag just meant "negative". Thank you dipole.
 
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