1. Buoyancy! Why Things Float!

2. Buoyancy The force that acts upwards on an object, opposite of gravitational force, on a floating object The force that acts upwards on an object, opposite of gravitational force, on a floating object The “push up” on the object (boyant forces) needs to be greater than the “push down” pull of gravity on an object or it will not float. The “push up” on the object (boyant forces) needs to be greater than the “push down” pull of gravity on an object or it will not float.

6. Buoyancy Cont’ The buoyant forces causing an object to float are equal in magnitude to the weight of the object (or the volume of water that it is displacing) The buoyant forces causing an object to float are equal in magnitude to the weight of the object (or the volume of water that it is displacing)

7. Center of Gravity The center of gravity that is pulling down on the boat is the center of the overall volume of the boat. The center of gravity that is pulling down on the boat is the center of the overall volume of the boat. However, the center of gravity changes as the boat rocks and rolls on the water. This can cause problems in controlling the boat. However, the center of gravity changes as the boat rocks and rolls on the water. This can cause problems in controlling the boat.

8. Archimedes’ Story What did he discover? What did he discover? How did he do it? How did he do it? What does it have to do with buoyancy? What does it have to do with buoyancy? What does it have to do with our boat building project? What does it have to do with our boat building project?