Here is an example I just recalled from Physics class years ago. The rate of fall of an object is 9.8 meters per second squared or something like that. I scaled it to work with the limited resolution of DOS. Anyways hope you have fun looking at the source code. You can use it for your class intro. Just don't tell the teacher you got it online! Besides you need to remember it in your work later on anyways if you are a Physics professional hehe
https://www.mediafire.com/folder/74fdpcwc71t21/004943