Question

If an object cools down from 80°C to 60°C in 5 min in a surrounding of temperature 20°C. The time taken to cool from 60°C to 40°C will be (Assume Newton’s law of cooling to be valid)

• A. $\frac{25}{3}$ min
• B. 5 min
• C. $\frac{25}{4}$ min
• D. 5 min

Answer 1

Answer: (A)

$\frac{25}{3}$ min

Answer 2

The correct option is (A): $\frac{25}{3}$ min