Question

if final temperature of two mixed liquids is given how to find in which ratio are they mixed

Answer 1

One of the primary laws of physics is the conservation of energy. You can see an example of this law in operations by mixing two liquids at different temperature and calculating the final temperature. Check the final temperature achieved in the mixture against your calculations. The answer should be the same if you assume that no energy was lost to the environment. The practical answer is different from the one you calculated because some heat is in fact lost to the surroundings. Look at how the calculation is performed, assuming that you mix two containers of water at different temperatures together.

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