Consider one-dimensional heat conduction through a large plane wall with no heat generation that is perfectly insulated on one side and is subjected to convection and radiation on the other side. It is claimed that under steady conditions, the temperature in a plane wall must be uniform (the same everywhere). Is this claim reasonable

YES, this claim reasonable

Explanation:

the temperature in a plane wall is uniform since no heat is penetrating into the large plane wall and therefore, there is no heat transfer from the wall under steady conditions,  

This condition will be met only when there are no temperature differences within the wall and the the outer surface temperature of the wall is equal to the temperature of its surrounding.

Therefore, Yes, this claim is reasonable

answer:

true

c

explanation: