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Heat flows between two bodies in contact until the system attains thermal equilibrium. What happens if the bodies in contact having different specific heat capacity and same temperature. Does the flow of heat occurs until the heat energy between the bodies become equal since the amount of heat need to rais the temperature is different?

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  • $\begingroup$ Heat is that form of energy which is transferred due to a temperature difference. $\endgroup$ – Farcher Nov 3 '16 at 19:38
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    $\begingroup$ No. Temperature is the correct variable, not heat content. Now, heat will flow between the two bodies - the question is whether there is net heat flow. $\endgroup$ – Jon Custer Nov 3 '16 at 19:38
  • $\begingroup$ Suppose you had two bodies, one the size of a grape and one the size of an ocean. Which makes more sense to you: at equilibrium (a) they should have the same amount of heat or (b) they should have the same temperature? $\endgroup$ – Chet Miller Nov 3 '16 at 20:08
  • $\begingroup$ @JonCuster right, I agree net heat flow is zero. But at any one moment the heat flow doesn't necessarily have to be zero. I suppose those two statements are true as long as the temperature is not absolute zero. $\endgroup$ – docscience Nov 3 '16 at 21:04
  • $\begingroup$ @docscience If at any moment the heat flow doesn't necessarily have to be zero, how does the heat know which way to flow? $\endgroup$ – Chet Miller Nov 4 '16 at 2:43
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May be an analogy will help. If two tanks containing water are connected by a pipe, water flows from the tank with higher level to that with lower level of water. Temperature is analogous to water level. Heat capacity is analogous to floor area of the tank. The tank with a larger floor area can hold greater amount of water (for a given water level), but that has nothing to with determining whether and in which direction water will flow.

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Simply a No.

There are so many ways to reason this. Suppose it's possible and the heat is transferred from object A, to object B, with initial temperature $T_A = T_B = T_o$. With heat transfer alone, $T_A$ decreases and $T_B$ increases.

Since you have two sources with different temperatures, you would be able to build an engine out of it. This, violates the second law of thermal dynamics.

Or simply, when they are of different temperatures, heat transfer will happen until they again reach the same temperature.

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