In the conduction equation Q = (kA?T)t/L, the combination of factors kA/L is cal
ID: 2067806 • Letter: I
Question
In the conduction equation Q = (kA?T)t/L, the combination of factors kA/L is called the conductance. The human body has the ability to vary the conductance of the tissue beneath the skin by means of vasoconstriction and vasodilation, in which the flow of blood to the veins and capillaries underlying the skin is decreased and increased, respectively. The conductance can be adjusted over a range such that the tissue beneath the skin is equivalent to a thickness of 0.095 mm of Styrofoam or 2.8 mm of air. By what factor can the body adjust the conductance??
Explanation / Answer
Conductance = 1/resistance = K*A/L Ls = 0.086 Ks = 0.010 La = 2.5 Ka = 0.0256 Cs/Ca = (Ks/Ka)*(La/Ls) =(0.010/0.0256)*(2.5/.086) =11.355