While playing ultimate there are many things I have to consider before I even let go of the disc. I have to know what direction the wind is blowing that way I can tilt the disc in the right direction so I can minimize air resistance. Not to mention I have to look out for defenders on the field, pretty obvious. The way defenders are positioned will also let me know how I have to curve the disc or what throw to use to get it past them to my receiver.
Now that I'm ready to throw the disc I have to decide an angle to throw the disc at to try and maximize distance, but that's also what my initial velocity comes in. While keeping in mind the air resistance from the first part, my goal is to throw it just ahead of my receiver which helps me decide the initial velocity whether I'm looking to huck it or just dump it.
Conclusion?! Physics is used in Ultimate too!