1. The problem statement, all variables and given/known data A spherical black body having R=0.1m and initial temperature T1=10^3 K is cooled by radiation.The surrounding medium is at a temperature T=0K.What time will it take for the temperature of the sphere to drop to T2=100K? Given heat capacity is C and density d The answer is : (CdR/9σ)(T2^(-3) - T1^(-3)) 2. Relevant equations 3. The attempt at a solution I think just application of Newton's law of cooling will suffice...Isn't it?