We estimate the buoyancy needed for an object using the formula B = ρ × V × g, where ρ and V are the object's density and volume, respectively, and g is the acceleration due to gravity. Water has a density of 1000 kg/m3. Thus, the buoyant force needed is 1000 kg/m3 × 1 L × 9.81 m/s2 = 9.81 N. Read more