1. The problem statement, all variables and given/known data Hi, For one of my physics projects i need the natural frequency, or frequency of oscillation of a ball. I don't even know where to start. I've got a short article of an experiment similar to mine where they also use this natural frequency. So if my story is unclear, which im sure it is, you can take a look and see if that makes it any clearer. http://www.fas.harvard.edu/~scidemos/OscillationsWaves/SaddleShape/SaddleShape.html Thanks in advance. 2. Relevant equations None so far 3. The attempt at a solution Also, none so far, as i don't understand it really, sorry.