It takes `10 minutes` to cool a liquid from `61^(@)C` to `59^(@)C`. If room temperature is `30^(@)C` then find the time taken in cooling from `51^(@)C` to `49^(@)C`.A. `4` minuteB. `6` minuteC. `5` minuteD. `8` minute

It takes `10 minutes` to cool a liquid from `61^(@)C` to `59^(@)C`. If

1.	It takes `10 minutes` to cool a liquid from `61^(@)C` to `59^(@)C`. If room temperature is `30^(@)C` then find the time taken in cooling from `51^(@)C` to `49^(@)C`.A. `4` minuteB. `6` minuteC. `5` minuteD. `8` minute
Answer» Rate of cooling `alpha` difference in temperature `(dT)/(dt) prop Delta theta rArr (dT)/(dt)=KDelta theta` `dT=KDelta theta.dt` In first case : `dT=61-59=2` `Deltatheta=60^(@)-30^(@)=30^(@)` `dt=4"minute"` `:. K=(dT)/(Deltatheta dt)=(2)/(30xx4)=(1)/(60)` For second case : `dT=2` `Deltatheta=50-30=20` `:. dt=(dT)/(KDeltatheta)=(2)/(.^(1)//_(60)xx 20)=6min`