1. http://commons.wikimedia.org/wiki/File:Buoyancy.svg#mediavi ewer/File:Buoyancy.svg In physics, Archimedes' principle says that any fluid exerts a buoyant force on an object wholly or partially submerged in it, and the magnitude of the buoyant force equals the weight of the fluid displaced by the object. An object that’s less dense than water floats because the water it displaces weighs more than the object does.

2. http://commons.wikimedia.org/wiki/File:Buoyancy.svg#mediavi ewer/File:Buoyancy.svg If you’ve ever tried to push a beach ball underwater, you’ve felt this principle in action. As you push the ball down, it pushes back up. In fact, a big beach ball can be tough to hold underwater. As a physicist in a bathing suit, you may wonder, “What’s happening here?”

3. The volume of displaced fluid is equivalent to the volume of an object fully immersed in a fluid or to that fraction of the volume below the surface for an object partially submerged in a liquid. http://www.britannica.com/EBchecked/topic/32827/Archimedes-principle

4. The weight of the displaced portion of the fluid is equivalent to the magnitude of the buoyant force. http://www.britannica.com/EBchecked/topic/32827/Archimedes-principlehttp://www.spaceflight.esa.int/users/materials/introduction/space/buoyancy.html

5. The buoyant force on a body floating in a liquid or gas is also equivalent in magnitude to the weight of the floating object and is opposite in direction; the object neither rises nor sinks. http://www.britannica.com/EBchecked/topic/32827/Archimedes-principle