A sphere of radius ' R 1 ' is enclosed in a sphere of radius ' R 2 '. The view (or shape) factor for radiative heat transfer of the outer sphere with respect to the inner sphere is

A sphere of radius ' R 1 ' is enclosed in a sphere of radius ' R 2 '.

1.	A sphere of radius ' R 1 ' is enclosed in a sphere of radius ' R 2 '. The view (or shape) factor for radiative heat transfer of the outer sphere with respect to the inner sphere is
A.	0
B.	R2 /( R 1 + R 2 )
C.	1
D.	( R 1 / R 2 ) 2
Answer» C. 1

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A sphere of radius ' R 1 ' is enclosed in a sphere of radius ' R 2 '. The view (or shape) factor for radiative heat transfer of the outer sphere with respect to the inner sphere is

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