A solid cylinder (surface 2) is located at the centre of

A solid cylinder (surface 2) is located at the centre of a hollow sphere (surface 1). The diameter of the sphere is 1 m, while the cylinder has a diameter and length of 0.5 m each.'The radiation configuration factor F₁₁ is

Diameter of sphere = 1 m
Diameter of aylinder = 0.5 m
F₂₁ + F₂₂ = 1 (∵ F₂₂ = 0)
F₂₂ = 1
we know that
A₁ F₁₂ = A₂ F₂₁

F₁₂ =	A₂
	A₁

∴ F₁₁ = 1 - F₁₂ = 1	- A₂
	A₁

∴ F₁₁ = 1 -	A₂
	A₁

F₁₁ = 1 -	[(π × 0.5 × 0.5) + ( 2 × π/4 × 0.5 × 0.5)]	= 0.625
	4π × 0.5 × 0.5