Water Safety Instructor (WSI) Practice Exam

The center of buoyancy represents the location of all upward force acting on a submerged or floating object. In the context of swimming physics, buoyancy is the upward force exerted by a fluid that opposes the weight of an object immersed in it. The center of buoyancy is determined by the shape and volume of the displaced fluid, which changes as a swimmer moves and alters their position in the water. When a swimmer is in a vertical or horizontal position, the center of buoyancy shifts according to the distribution of their body mass and how much water they displace. The upward force of buoyancy helps to counteract the weight of the swimmer, allowing them to float or remain suspended in the water. Understanding the center of buoyancy is critical for swimmers to maintain good body position and optimize their efficiency in the water. The other options do not correctly capture the definition of the center of buoyancy. The downward force configuration, swimming efficiency, and drag resistance are related concepts but do not accurately define the center of buoyancy itself.