Physics-
General
Easy
Question
A liquid cools down from 
to 
in 5 minutes. The time taken to cool it from to 
will be
- 5 minutes
- Lesser than 5 minutes
- Greater than 5 minutes
- Lesser or greater than 5 minutes depending upon the density of the liquid
The correct answer is: Greater than 5 minutes
According to Newton’s law of cooling
Rate of cooling 
mean temperature difference
Initially, mean temperature difference
Finally, mean temperature difference
In second case mean temperature difference decreases, so rate of fall of temperature decreases, so it takes more time to cool through the same range
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