In a room where temperature is {30^o}C , a body cools from {61^o}C to {59^o}C in 4 minutes. time (in

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10-2.Transmission of Heat

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In a room where the temperature is ${30^o}C$, a body cools from ${61^o}C$ to ${59^o}C$ in $4$ minutes. The time (in min.) taken by the body to cool from ${51^0}C$ to ${49^0}C$ will be ....... $\min$

A$4$

B$6$

C$5$

D$8$

Solution

(b) First case, $\frac{{61 – 59}}{4} = K\left[ {\frac{{61 + 59}}{2} – 30} \right]$…..$(i)$
Second case, $\frac{{51 – 49}}{t} = K\left[ {\frac{{51 + 49}}{2} – 30} \right]$ …..$(ii)$
By solving equation $(i)$ and $(ii)$ we get
$t = 6 min$ .

Standard 11

Physics

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In a room where the temperature is ${30^o}C$, a body cools from ${61^o}C$ to ${59^o}C$ in $4$ minutes. The time (in min.) taken by the body to cool from ${51^0}C$ to ${49^0}C$ will be ....... $\min$

Solution

Similar Questions

The temperature of body is increased from $27\,^oC$ to $127\,^oC$ the radiation emitted by it increases by a factor of

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