we know that $\Delta U$ $=$ $\Delta K_{cm}$ $+$ $\Delta I$(adsbygoogle = window.adsbygoogle || []).push({});

where $\Delta K_{cm}$ is the kinetic energy from cm frame of refrence and the other part is the change in change in potential energy due to various conservative forces.

also by first law of thermodynamics $\Delta U$ $=$ $W_{ext} + Q$

can we define $W_{ext}$ and $Q$ in terms of the other variables kinetic energy and potential energy

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# Basic thermo problem

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