Definition

Force resulting from the upward pressure of water, acting upon the immersed volume of a body, set against the total WEIGHT of such body. If the volume immersed is such that the upward pressure counterbalances the WEIGHT of the body, the buoyancy is said to be positive and the body floats on the surface; if the volume immersed is insufficient, the weight of the body is greater than the upward pressure, the buoyancy is negative, and the body sinks.