Two friends A and B are waiting for another f | vedclass

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(A) According to Newton's Law of Cooling,the rate of heat loss is proportional to the temperature difference between the object and its surroundings,i

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(A) According to Newton's Law of Cooling,the rate of heat loss is proportional to the temperature difference between the object and its surroundings,i.e.,$\frac{dQ}{dt} \propto (T - T_s)$.In case of friend $A$,the cold milk is added immediately. This lowers the initial temperature of the tea mixture. Since the temperature difference between the mixture and the surroundings is smaller,the rate of heat loss is lower.In case of friend $B$,the tea remains at a higher temperature for a longer duration before the cold milk is added. Because the temperature difference between the hot tea and the surroundings is larger,the rate of heat loss is higher.Therefore,the tea in the cup of friend $A$ will remain hotter when the friend arrives.

Two friends $A$ and $B$ are waiting for another friend for tea. $A$ took the tea in a cup and mixed the cold milk and then waits. $B$ took the tea in the cup and then mixed the cold milk when the friend comes. Then the tea will be hotter in the cup of

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