The heat flow equation through a cylinder of inner radius r1 and outer radius r2 is desired to be written in the same form as that for heat flow through a plane wall. For wall thickness (r₂-r₁) the area will be

The heat flow equation through a cylinder of inner radius r1 and outer

1.	The heat flow equation through a cylinder of inner radius r1 and outer radius r2 is desired to be written in the same form as that for heat flow through a plane wall. For wall thickness (r₂-r₁) the area will be
A.	A1 + A2/2
B.	A1 + A2
C.	A2 – A1/ log e (A2/A1)
D.	A1 + A2/2 log e (A2/A1)
Answer» B. A1 + A2

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The heat flow equation through a cylinder of inner radius r1 and outer radius r2 is desired to be written in the same form as that for heat flow through a plane wall. For wall thickness (r₂-r₁) the area will be

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