Q.

A body initially at 80°C cools to 64°C in 5 minutes and to 52°C in 10 minutes. The temperature of the body after 15 minutes will be

Moderate

Unlock the Full Solution and Master the Concept

Get a detailed solution and exclusive access to our masterclass to ensure you never miss a concept

By Expert Faculty of Sri Chaitanya

42.7°C

35°C

47°C

40°C

answer is 1.

(Detailed Solution Below)

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Detailed Solution

According to Newton's law of cooling, θ1−θ2t=Kθ1+θ22−θ0 For first process: (80−64)5=K80+642−θ0 …(i)For second process: (80−52)10=K80+522−θ0 …(ii)For third process: (80−θ)15=K80+θ2−θ0 …(iii)On solving Eqs. (i) and (ii), we getK=115 and θ0=24∘CPutting these values in Eq. (iii), we getθ=42.7∘C.

Choose your Grade and Exam

Connect with our

Expert Counsellors

access to India's best teachers with a record of producing top rankers year on year.

+91

We will send a verification code via OTP.