Inspired by a conversation with Andrew Shauver (@hs_math_phys) trying to think of situations for related rates. I thought maybe the distance you can see from a Ferris Wheel as it turns. Searching YouTube I found this great video of a double Ferris Wheel... so then you want to model it!
Video: [url]http://youtu.be/ec6b6NHJMPw[/url]
