Question

What is the physical interpretation of the Biot number?

Answer 1

Biot number is defined as the ratio of heat convection to surface to the heat conduction called biot number

And small biot number indicate small resistance to the heat conduction because of which there small temperature gradient within the body

Biot number is used in lumped systems analysis when the thermal conductivity of material is very high when biot number is less than 0.1 than lumped systems analysis is applicable when bi=0 then lumped analysis is exact when it is greater the lumped systems is not applicable