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  1. The problem statement, all variables and given/known data:

A certain mass m of water in a copper pot is heated over a stove that releases Q joules of heat to heat the water. Later the same mass m of water in an aluminum pot is heated over another stove that releases the same amount of heat Q in order to heat the water. Then the water in which pot will have the higher final equilibrium temperature?

  1. Relevant equations: Q = mc∆T

  2. The attempt at a solution: I think the final temperature of the water in the metal pot with the least specific heat will be higher because that pot can transfer heat more easily. Is this correct?

(Edit) I believe you heat both of the pots for the same amount of time (not long enough to boil) and then stop the stove. Then wait until the equilibrium temperature for the metal and water is reached and compare it for both of them.

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  • $\begingroup$ Well it depends on when you stop your experiment. In both cases water will boil at the same temperature but it will not take the same time. But here final as no sense, you need to be more precise. $\endgroup$ – Hexacoordinate-C Nov 11 '17 at 0:51
  • $\begingroup$ I believe you heat both of the pots for the same amount of time (not long enough to boil) and then stop the stove. Then wait until the equilibrium temperature for the metal and water is reached and compare it for both of them. $\endgroup$ – mihirb Nov 11 '17 at 0:53
  • $\begingroup$ @Hexacoordinate-C "Final" means "when both plates have given off the amount of heat Q". That's what the problem states, can't get any more precise than that. $\endgroup$ – Karl Nov 11 '17 at 10:30
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You are right of course, but not perfectly in your reasoning.

The transfer of heat is not the point, because the question already says it is $Q$ in both cases, not $0.9 Q$ in one and $1.2 Q$ in the other. Pot and water have the same temperature ("equillibrium"). That's of course nonsense (bottom of pot would obviously be hotter than the rest in reality) but you have to stick to the made-up facts your teacher gave you.

Both plates have given off the same amount of heat(energy), so the pot with less heat capacity is hotter.

Note: This is a Gedankenexperiment. Don't make the error to think up an actual setup with a stopwatch, thermometer and power meter. For example the plate would also give off heat to it's stand and surrounding air, how could you measure that?

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