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In a room maintained at 30°C, a body falls in temperature from 61°C to 59°C in 4 minutes. How many minutes will it take for the same body to drop from 51°C to 49°C?

1. 8
2. 6
3. 4
4. 2

Correct answer: 6

Solution

The cooling process follows Newton's Law of Cooling, which states that the rate of temperature change is proportional to the difference between the object's temperature and the ambient temperature. Since the temperature difference decreases as the body cools, it will take longer to drop from 51°C to 49°C than from 61°C to 59°C, resulting in a time of 6 minutes.

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