1 Buoyancy (also known as the buoyant force) is the force exerted on an object that is wholly or partly immersed in a fluid. 2  The symbol for the magnitude of buoyancy is B or FB.3  As a vector it must be stated with both magnitude and direction. Buoyancy (also known as the buoyant force) is the force exerted on an object that is wholly or partly immersed in a fluid. 2  The symbol for the magnitude of buoyancy is B or FB.
epicenter. 1  Also, epicentrum. Geology. a point, directly above the true center of disturbance, from which the shock waves of an earthquake apparently radiate. 2  a focal point, as of activity: Manhattan's Chinatown is the epicenter of the city's Chinese community.
The focus, or hypocenter, is the point beneath earth's surface atwhich rock under stress breaks and triggers and earthquake. Incontrast, the epicenter is the point on the eaâ¦rth's surfacethat is directly above the focus or hypocenter.