A body cools from 40°C to 24°C in 4 min in surroundings at 16°C. Using the same Newton's-law-of-cooling approximation as the source solution, its temperature after a further 4 min is:
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A body cools from 40°C to 24°C in 4 min in surroundings at 16°C. Using the same Newton's-law-of-cooling approximation as the source solution, its temperature after a further 4 min is:

G1 Physics · Accepted Answer

Using the source's average-temperature form of Newton's law of cooling: for the first interval, (40-24)/4=b[(40+24)/2-16]=16b, giving b=1/4. For the next interval, (24-T)/4=(1/4)[(24+T)/2-16]. Solving gives T=56/3 °C.