Shape factor for sphere is

1.	Shape factor for sphere is
A.	4 π r₁ r₂
B.	4 π r₁ r₂/r₂ – r₁
C.	4 π /r₂ – r₁
D.	r₁ r₂/r₂ – r₁
Answer» C. 4 π /r₂ – r₁

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Shape factor for sphere is

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