GATE Mechanical Engineering (ME) 2021 Shift 1 Solved Paper

A solid sphere of radius 10 mm is placed at the centroid of a hollow cubical enclosure of side length 30 mm. The outer surface of the sphere is denoted by 1 and the inner surface of the cube is denoted by 2. The view factor F22 for radiation heat transfer is _______ (rounded off to two decimal places).