Question

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 0.600m^3 and the tension in the cord is 840N . What is the mass of the sphere? And Calculate the buoyant force exerted by the water on the sphere.

Answer 1

Tension=bouyant force-mg=volume*densitywater*g-mg
= you do it.