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Question
Should the internal energy of a system necessarily increase if its temperature is increased?
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Solution
Internal energy of a system increases if its temperature increases. This is valid only for the system of ideal gases and not for all the systems.
For example:- During meting process, temperature of the system remains constant, but internal energy change increases by mL.
⇒ ΔU = mL
Here,
m = Mass of the solid
L = Latent heat of the solid
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