Newton's Law of Cooling (not the formal definition):(adsbygoogle = window.adsbygoogle || []).push({});

(change in time) = -ln ((Tf - S)/(Ti - S)) / k

Tf = final temperature

Ti = initial temperature

S = temperature of environment

k = heat transfer coefficient

Say that you wanted to cool something (such as a person) to a negative temperature (Tf would be negative) and the temperature of the environment was positive. This would mean that you would have to take the -ln (-#). Obviously, you can't do this. In another situation, say the surrounding temperature was the same as the final temperature. This would mean that you would have to take the -ln (0) which can't be done. How can I apply this formula to these situations?

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# Newton's Law of Cooling Flawed?

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