Consider two hot bodies ${B_1}$ and ${B_2}$ which have temperatures ${100^o}C$ and ${80^o}C$ respectively at $t = 0$. The temperature of the surroundings is ${40^o}C$. The ratio of the respective rates of cooling ${R_1}$ and ${R_2}$ of these two bodies at $t = 0$ will be
A${R_1}:{R_2} = 3:2$
B${R_1}:{R_2} = 5:4$
C${R_1}:{R_2} = 2:3$
D${R_1}:{R_2} = 4:5$
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A${R_1}:{R_2} = 3:2$
a (a) Initially at $t = 0$
Rate of cooling $(R)$ $\propto$ Fall in temperature of body ($\theta -\theta_0$)
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