My cousin, Madi, was rocking back and forth in her rocking chair. A rocking chair is an example of simple harmonic motion because it is a repetive movement back and forth at an equilibrium position. An equilibrium position is where the maximum displacement on one side is equal to the maximum displacement on the other. The force of the motion is always aimed at the equilibrium position. Later, another of my younger cousins was pushing her and he accidentally pushed her too hard! Through falling, she became a projectile because she traveled both vertically and horizontally through the air. Everyone was freaking out because it looked like a really bad fall, but luckily she was OK. I don't think she'll be allowed to sit on any more rocking chairs any time soon though!