The thermal resistance for heat conduction through a hollow sphere of inner radius r1 and outer radius r2 is

The thermal resistance for heat conduction through a hollow sphere of

1.	The thermal resistance for heat conduction through a hollow sphere of inner radius r1 and outer radius r2 is
A.	r₂ – r₁/4πk r₁r₂
B.	r₂ /4πk r₁r₂
C.	r₁/4πk r₁r₂
D.	4πk r₁r₂
Answer» B. r₂ /4πk r₁r₂

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The thermal resistance for heat conduction through a hollow sphere of inner radius r1 and outer radius r2 is

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