So you want the upper edge of each circle to be exactly on the hemisphere?
See this (sorry for the quick and dirty sketch), where h is the height of all the discs up to that point (including the one you want to find the radius of), and r is the radius of the hemisphere you're looking for.
So you want the upper edge of each circle to be exactly on the hemisphere?
See this (sorry for the quick and dirty sketch), where h is the height of all the discs up to that point (including the one you want to find the radius of), and r is the radius of the hemisphere you're looking for.