Explain Why Two Bodies at Different Temperatures T1 And T2 If Brought in Thermal Contact Do Not Necessarily Settle to the Mean Temperature (T1 + T2)/2. - Physics

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Explain why Two bodies at different temperatures T1 and T2, if brought in thermal contact, do not necessarily settle to the mean temperature (T1 + T2)/2.

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Solution 1

When two bodies at different temperatures T1 and T2 are brought in thermal contact, heat flows from the body at the higher temperature to the body at the lower temperature till equilibrium is achieved, i.e., the temperatures of both the bodies become equal. The equilibrium temperature is equal to the mean temperature (T1 + T2)/2 only when the thermal capacities of both the bodies are equal.

Solution 2

In thermal contact, heat flows from the body at higher temperature to the body at lower temperature till temperatures become equal. The final temperature can be the mean temperature (T1+ T2)/2 only when thermal capacities of the two bodies are equal.

Concept: Heat, Internal Energy and Work
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Chapter 12: Thermodynamics - Exercises [Page 316]

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NCERT Physics Class 11
Chapter 12 Thermodynamics
Exercises | Q 3.1 | Page 316

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