Question

A body cools from 70°c to 60 °c in 5 minute and to 45°c in next 10 minute calculate tha temperature of surrounding

Answer 1

$\frac{T2-T1}{time} = K[\frac{T1+T2}{2}+ Ts]$

Ts = surrounding temperature

From given data

$\frac{10}{5} = K [65 - Ts]$

$\frac{15}{10} = K [52.5-Ts]$

By dividing both eqns we have

$\frac{4}{3}= \frac{65-Ts}{52.5-Ts}$

$210-4Ts = 195 - 3Ts$

Ts = 15°C