A wall consists of 2 layers of material: brick in front of an equal thickness of wood. If the respective thermal conductivities of the brick and wood are 1.3 J/m-s-C and 0.15 J/m-s-C,
how does the temperature gradient across the wood compare to the gradient across the brick?
?Tw/?Tb = kb/kw = 1.3 / 0.15 = 8.7
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