Thermodynamics: Dropping a hot horseshoe into a pot of water

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The discussion focuses on calculating the heat transfer when a hot horseshoe is dropped into a pot of water. The initial temperature of the horseshoe is 261.5 °C, and after reaching thermal equilibrium with the pot and water, the final temperature is 29.8 °C. The heat gained by the water is calculated as 56179.2 J, and for the pot, it is 1062.18 J, leading to a total heat gain of 57241.38 J. There is a clarification regarding the rounding of the final answer to three significant figures, indicating that the initial rounding may not have been accurate. The final heat transfer calculation is confirmed as correct at 57241.38 J.
Jess_18033152
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Homework Statement


A freshly-forged iron horseshoe, with a mass of 0.549 kg is dropped into a 0.281 kg iron pot which contains 1.60 kg of water at 21.4 oC.
After the horseshoe, pot and water reach thermal equilibrium they have a temperature of 29.8 oC.

Assuming the pot and the water were in thermal equilibrium before the horseshoe entered the water, calculate the combined amount of heat gained by the pot and water as they cool the horseshoe.

From previous question:
Initial temp of horseshoe = 261.499575 degrees C
Q (water) = 56179.2 J
Q (pot) = 1062.18 J

Homework Equations


Q= mc (change in temp)

The Attempt at a Solution


Q (horseshoe) = 0.549 x 450 x (261.499575-29.8)
= 57241.38 J

Q (water) = 56179.2 J
Q (pot) = 1062.18 J
Q (pot & water) = 56179.2 + 1062.18
= 57241.38 J

Am I heading in the right direction to calculate the combined amount of heat gained by the pot and water as they cool the horseshoe?
 
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Worked out that the answer for this question is just = 57241.38 J rounded to 3 significant figures. :)
 
Jess_18033152 said:
Worked out that the answer for this question is just = 57241.38 J rounded to 3 significant figures. :)
Do you really feel that that is rounded to 3 significant figures?
 
Sorry, that my answer from that I rounded to 3 sf so that wasn't my final answer as it is not 3 sf
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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