> The basic idea is that the thermal time constant of a uniform sphere (or other shape of fixed aspect) is proportional to the square of its radius. Shouldn't

> The basic idea is that the thermal time constant of a uniform sphere (or other shape of fixed aspect) is proportional to the square of its radius. Shouldn't the thermal mass go like volume (radius cubed) while the power conducted away go like surface area (radius squared) so the time to cool should go like mass/power ~ volume/area, so linearly in radius?