A hollow metallic sphere of radius 20cm surrounds a concentric metallic sphere of radius 5cm.
Channel: Doubtnut
Date: 2020-07-12

A hollow metallic sphere of radius 20cm surrounds a concentric metallic sphere of radius 5cm. The space between the two sphere is filled with a nonmetallic material. The inner and outer sphere are maintained at `50^(@)C` and `10^(@)C` respectively and it is found that 100J of heat passes from the inner sphere to the outer sphere per second. Find the thermal conductivity of the material between the sphere.