How does a life jacket keep an unconscious person's head out of the water?

A life jacket is designed to provide buoyancy and stability in the water. Its inherent flotation features, typically made from buoyant foam or inflatable materials, help keep the wearer afloat. In the case of an unconscious person, the life jacket's design helps to automatically position the body face-up, allowing the head to stay above the water, which minimizes the risk of drowning. This is achieved through a combination of buoyancy and the shape of the life jacket, which promotes proper orientation in the water.