A hollow plastic sphere is held below the surface of a freshwater lake by a cord anchored to the bottom of the lake. The sphere has a volume of 0.700m^3 and the tension in the cord is 800N .
Part A Calculate the buoyant force exerted by the water on the sphere.
Part B What is the mass of the sphere?
Part C The cord breaks and the sphere rises to the surface. When the sphere comes to rest, what fraction of its volume will be submerged?