1. The problem statement, all variables and given/known data Styrofoam has a density of . What is the maximum mass that can hang without sinking from a 20.0 -diameter Styrofoam sphere in water? Assume the volume of the mass is negligible compared to that of the sphere. 2. Relevant equations FB = ρfVg Fg = mg 3. The attempt at a solution So this is as far as I can get. The buoyancy force on the sphere is FB = ρfVg = 1000kg/m3 * pi * 0.22 * 9.8 = 333.54. However we need to take into account the weight of the sphere. The weight of the sphere = ρ*V = 300*pi*0.22 = 10.2 This means the net weight on the sphere is Fnet = 333.54 - (10.2*9.8) = 233.54 So the maximum weight that can be hung on the sphere must have a downward force of precisely that. mg = 233.54. m = 23.8kg. But apparently thats not it, any pointers?