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(A) According to Newton's law of cooling,the rate of loss of heat is given by: $\frac{dQ}{dt} = mc \frac{d	heta}{dt} = -kA(	heta - 	heta_0)$.Thus,t

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(A) According to Newton's law of cooling,the rate of loss of heat is given by: $\frac{dQ}{dt} = mc \frac{d	heta}{dt} = -kA(	heta - 	heta_0)$.Thus,the rate of cooling is $\frac{d	heta}{dt} = -\frac{kA}{mc}(	heta - 	heta_0)$.Since the mass $m$,surface area $A$,and surface finish (emissivity $k$) are the same for both bodies,the rate of cooling $\frac{d	heta}{dt}$ is inversely proportional to the specific heat $S$.Given $S_A > S_B$,it follows that $\left| \frac{d	heta}{dt} ight|_A This means body $A$ cools more slowly than body $B$.Therefore,the graph where the curve for $A$ is above the curve for $B$ (indicating a slower drop in temperature for $A$) is the correct representation.

Two bodies $A$ and $B$ of same mass,area,and surface finish with specific heats $S_A$ and $S_B$ $(S_A > S_B)$ are allowed to cool for a given temperature range. The temperature varies with time as shown in the graphs. Which graph correctly represents the cooling process?

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