This is my project for AP Physics. I had to take a picture that represents a physics principal. My photo demostrates center of gravity:
This project represents the concept of center of gravity. While at first, the spoon and fork look unbalanced in comparison to their position in the toothpick and the toothpick’s position on the rim of the glass, they actually are. This is because the center of gravity of the spoon and fork is exactly on the rim.
By definition, the center of gravity is the average location of all mass in a system. It is the center of mass rather than geometric center. This is why the photo looks odd. Clearly the geometric center of the system is not at the tip of the toothpick on the rim of the glass; however, the center of mass is.
The center of mass of a system is calculated by dividing the sum of the positions times weight by the sum of the weights. So in this case, if the fork-spoon-cup-toothpick system were graphed on a coordinate plane, the location R (center of gravity) would be exactly where the burnt end of the toothpick is, on the glass.
