A body cools in $7$ minutes from ${60^o}C$ to ${40^o}C$ What time (in minutes) does it take to cool from ${40^o}C$ to ${28^o}C$ if the surrounding temperature is ${10^o}C$? Assume Newton’s Law of cooling holds
Medium
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(c) In first case $\frac{{60 - 40}}{7} = K\left[ {\frac{{60 + 40}}{2} - 10} \right]$….$(i)$
In second case $\frac{{40 - 28}}{t} = K\left[ {\frac{{40 + 28}}{2} - 10} \right]$….$(ii)$
By solving $t = 7$ $minutes$
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