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suchjoe
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Homework Statement
When 1.70 ✕ 105 J of heat enters a cherry pie initially at 20.0°C, its entropy increases by 470 J/K. What is its final temperature?
Homework Equations
The Attempt at a Solution
I have no clue
Sorry, but you have to try something. Do you know the equation for how the heat that enters is related to the temperature rise? Do you know the equation for how the entropy change is related to the initial and final temperatures. Both these equations involve the heat capacity.suchjoe said:Homework Statement
When 1.70 ✕ 105 J of heat enters a cherry pie initially at 20.0°C, its entropy increases by 470 J/K. What is its final temperature?
Homework Equations
The Attempt at a Solution
I have no clue
suchjoe said:Homework Statement
When 1.70 ✕ 105 J of heat enters a cherry pie initially at 20.0°C, its entropy increases by 470 J/K. What is its final temperature?
Homework Equations
The Attempt at a Solution
I have no clue
Something like the last equation is the one to use, but I'm sure they want you to assume that the heat capacity is constant. You don't need to know the surroundings temperature, so don't waste your time looking for that.wreckemtech said:Generally, S = Q/T. Kind of simplistic, but that is probably what you're going to use to find the net heat transfer into the cherry pie. Then, you'll need to know the heat capacity of the cherry pie to determine the change in temperature. Does the problem statement give the temperature of the surroundings? If so, I'd use that as the temp at which the heat transfer occurs. And if this is a college thermo class, dS = Cavg*ln(t2/t1)
According to PF rules, we really shouldn't be doing the problem for suchjoe. We should just be giving him little hints so that he can analyze it for himself. I feel like I've already revealed too much about how to do it.wreckemtech said:You know, I somehow completely missed the fact that Q was given in the problem statement. I thought the poster was only given T1 and dS. If Q is known, it should be easy enough to substitute something like Q=C(T2-T1) into the first equation, and then C will cancel.
wreckemtech said:Sorry. I'm new here.
"Cherry Pie Entropy" is a hypothetical scenario used in thermodynamics to help explain the concept of entropy. It involves a closed system consisting of a cherry pie and its surroundings, where heat is added to the pie and its entropy increases.
The final temperature of the cherry pie is determined using the formula: ΔS = Q/T, where ΔS is the change in entropy, Q is the heat added to the pie, and T is the final temperature.
In thermodynamics, heat and entropy are directly proportional to each other. This means that as heat is added to the cherry pie, its entropy will also increase.
Entropy is a fundamental concept in thermodynamics and has many real-world applications. It helps explain why certain processes are irreversible and why energy tends to disperse and become less useful over time.
While the Cherry Pie Entropy scenario is a simplified example used for educational purposes, the principles and equations involved can be applied to solve practical problems in thermodynamics and other fields such as chemistry and engineering.