In this project we investigated the physics of the forehand Frisbee throw. We decided to choose this sports action because many people don't know how to throw a Frisbee in this fashion and we thought people could actually learn something from our video. Before filming, we decided what we wanted to explain and demonstrate in out video by story-boarding and scripting. We decided that we wanted to calculate the velocity of the Frisbee while in the air and we wanted to explain angular momentum with calculations. We also wanted to explain the concept of air resistance on the Frisbee with Bernoulli's principle. For demonstrations, we decided to show proper stance, grip, the wrist snap and the angle of the frisbee to the ground.
Calculations and Concepts:
This is all of the concepts that we had in our video. You can read them all here or just view our video.
We calculated the velocity of the frisbee after being released.This gave us a horizontal velocity of 10.7 m/s. We found that the highest point of our throw was about 1.5 meters and it took 1.16 seconds to land on the ground. This gave us a vertical velocity of 1.2 m/s. Using the vector diagram shown in our video, we can figure out that the total velocity is 10.8 m/s which is about 24.15 mph.
Grip is also a huge part in the throw. When holding the frisbee, you want to make a gun with your hand and put your thumb on the top of the frisbee and your index and middle finger on the inside. For a visual demonstration, watch our video.
When throwing a frisbee, both your feet should be shoulder width apart and pointing the direction you are throwing. This ensures proper momentum transfer and direction.
We also used concepts to explain air resistance. If there were no air resistance, gravity would make the frisbee accelerate downwards at 9.8m/s2. However, because of the frisbee’s shape and the fact that it’s spinning, the air moves faster over the top of the disc than the bottom creating low pressure above the disc and higher pressure below. This helps keep the disc in the air for longer, allowing someone to run to it and catch it. The air resistance keeps the frisbee in the air longer, making it easier to catch. This is how an airplane’s wing works as well.
The frisbee should also be angled slightly towards the ground, because it will angle to the sky when thrown. If you start with it slightly angled to the ground, it with level out when thrown.
Snapping your wrist hen throwing the frisbee makes the frisbee spin. As the frisbee spins, it gains angular momentum(p). We calculate momentum by mass times velocity.(p=mv) If the momentum(p) increases, velocity has to increase to keep the equation equal. This is because mass will always be 0.175 kg, so the only way for mass times velocity to increase is if the velocity increases.
Reflection
I felt that our group did very well during this project. At the beginning we had trouble deciding what sports action to research and we didn't have very good time management. However, during the project we developed a better sense of time management and we finished with over a day left to slightly critique our video.
A peak is something our group did well. One peak of our project is that I think that we made our video flow really well. We had a mix of concepts, demonstrations, and then math problems so our viewers wouldn't get bored. If we just had math problem after math problem, our viewers would get bored. Also, I think that people need visual demonstrations to learn a concept, especially a sports action.
Another peak is that during the project, we also learn how to manage our time better. This was probably the best skill I learned from this project. We didn't spend our time wisely in the beginning; we spent a lot of time throwing frisbees around. When we realized that we only had two days left, we started working harder and we finished the rest of our video in under a day.
A pit is something we could have improved on. One thing that we could have improved on was our ability to compromise. In the beginning, we could not all agree on one sports action to do. We finally came to a conclusion that still didn't satisfy everyone, but it worked in the end. I learned that sometimes people need to compromise or you won't get anything done, sort of like how our government works. If the Republicans and Democrats can't agree, nothing gets done.
Another pit was deciding on the best clips for our video. It was hard to decide what clips to use and what clips to get rid of, because we thought our video was too long. However, we improved our video with the variety of demonstrations. This made it less boring. Next time I think we need a clearer storyboard that has times listed as well.
Not only did this project help us understand physics and important concepts such as momentum, we also learned from other subjects areas as well. The main part of this project was to focus on a sports action. This links the project to physical education. We also had to write a script and writing is a part of English. We also connected science with math and writing with film. I feel like this was a very successful project, and I learned a lot.