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Question
Should the internal energy of a system necessarily increase if heat is added to it?
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Solution
Change in internal energy of a system, `Delta U=C_vDeltaT`
Here,
Cv = Specific heat at constant volume
ΔT = Change in temperature.
If ΔT = 0, then ΔU = 0, i.e. in isothermal processes, where temperature remains constant, the internal energy doesn't change even on adding heat to the system.
Thus, the internal energy of a system should not necessarily increase if heat is added to it.
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