Yo-yos

During my elementary school years, I loved to play with yo-yos. I had the whole collection from the machine ones to those super long sleeping fat ones so that I could do as many tricks as I wanted to do without worrying that it will jump up and hit my face. I remember doing tricks such as walk the dog, eiffel tower, and around the world. Doing the "around the world" trick is an example of uniform circular motion if I kept swinging the yoyo in a circle around my head. The string provides the tension and is the centripetal force since it pulls the yoyo radially inward ( the term doc uses over and over again). Thus, Tsin(theta) is equal to (mv^2)/R, where m is the mass, v is the velocity, and R is the radius of the circle that I am creating when I swing the yo-yo. Also, weight also has an effect on the yoyo. The weight, mg, is equal to Tcos(theta), where T is equal to the tension and theta is the angle created by the string and my arm. Cool stuff.