Question

A bucket full of hot water cools from 75^0C to 70^0C in time T₁, from 70^0C to 65^0C in time T₂ and from 65^0C to 60^0C in time T₃, then

• A. $T_{1} = T_{2} = T_{3}$
• B. $T_{1} > T_{2} > T_{3}$
• C. $T_{1} < T_{2} < T_{3}$
• D. $T_{1} > T_{2} < T_{3}$

Answer 1

Answer: (C)

$T_{1} < T_{2} < T_{3}$

Answer 2

According to Newton's law of cooling rate of cooling depends upon the difference of temperature between the body and the surrounding. It means that when the difference of temperature between the body and the surrounding is small then time required for same fall in temperature is more in comparison with the same fall at higher temperature difference between the body and surrounding. So according to problem T₁ < T₂ < T₃.