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.
Epicenter of an earthquake The point where the rocks actually break is the earthquake focus. Large subduction zone earthquakes can break along a fault for hundreds of kilometer. The epicenter of these earthquakes is directly above where the earthquake actually started along the fault line. Destruction at the epicenter. The amount of destruction at the epicenter of an earthquake is directly affected by its size and the depth where the rocks rupture. The epicenter of an earthquake is the same whether the rocks ruptured at 50 kilometers, 100 kilometers or even 300 kilometers beneath the Earth's surface.