physics of sports video

Introduction

For this project me and my group focused our interests on the physics of pirouette we began this project learning what pirouette was and focusing on the physics of one full rotation. We took lots of videos and calculated the measurements based upon the average size of a ballerina (5ft. 8in.) Our goal was to be able to find the total force needed to perform this move so we could help others be able to achieve the same goal.

Velocity

We started by taking our horizontal velocity (0.71meters/second) Next we found our horizontal velocity being 0.25 m/s because that the size of an average ballerinas foot, and therefore the ballerina will rise that much. Lastly we had to find our total velocity which involved doing the pythagorean theorem and that gave us 0.8 m/s as our total velocity the same as 1.7 miles per hour.

Inertia

To find inertia you need two things mass and radius, luckily our radius had already been found when finding horizontal velocity. It was 0.7 meters and the average mass of a ballerina is 48 kilograms. Next we found the equation of rotational inertia: Inertia is equal to mass times radius squared, so by substituting our values we achieved 12.1 kilograms per meter squared.

Force

To find force we had to find the the mass which is 48 kg. Next the acceleration due to gravity (9.8 meters per second.) We were able to find the force used by the equation F=ma which resulted as 477.3 Newtons the same amount of weight as your average toilet. The next thing we calculated was Force of impact this involved multiplying mass and velocity then dividing it over the total time the pirouette was performed. The equation worked like this m*v=F*t F= force of impact and after calculating ended up with a total of 6.4 Newtons. In the end this means that when doing a pirouette use about 107 pounds of force when leaving and spin at 0.8 m/s or at 1.7 mph.

Reflection

Two things I believe I did was work through the struggles of doing a different sport unlike other groups and finding a way to learn new skills that benefited me during this project like having to do lost of research about ballerinas, as well as try and learn about this new sport and work out of my comfort zone.

Two things I want to keep on doing in the future is work out of my comfort zone by trying to do different sports and try and work on editing more.Also I like to challenge my self to grasp new ideas and understandings of sports like in this project.