Acylindrical log 18 cm in diameter and 75 cm long is glowing red hot in a fireplace. if it's emitting radiation at the rate of 38 kw , what is its temperature? the log's emissivity is essentially 1

To calculate the temperature of the log we need the Stefan-Boltzmann's law:

P=A*ε*σ*T⁴, where P is the power emitted by the body,
A is the total surface area of the body, in our case it is a cylinder so A=r²π*h where r is the radius of the base of the cylinder and h is the height of the cylinder, 
σ is the Stefan-Boltzmann constant, T is temperature and ε is emissivity .
Here we are approximating the log to be a black body. 

The area of the cylinder:

A=r²*π*h, r=d/2=0.75/2=0.375 m, where d is the diameter, h=0.18 m

A=0.07948 m²

Lets solve the equation for temperature T:

T⁴=P/(σ*ε*A) and take the 4th root to get T:

T=⁴√{P/(σ*ε*A)}=⁴√{38000/((5.67*10^-8)*1*0.07948)} = ⁴√(8.432*10^12)= 1704.06 C

So the temperature of the log is T= 1704 C

Iread this book last year so take this with a grain of salt.gene jumps from the tree to compete with finny due to the fact that gene is always trying to do better than finny. he is put under the grasp of peer pressure due to finny almost forcing him to do this. ever since he first jumped finny kept pressuring him to jump since he thought gene enjoyed jumping.rather than uses this answer you should probably just reread chapters 3-4