Physics |
Trebuchet Project
In this project we built trebuchets to launch projectiles as far as we could. We worked in groups of 3-5 to design, construct, test and refine a trebuchet. To complete this challenge we took inspiration from other designs in the world and used various physics concepts including gravity, acceleration, projectile motion and kinetic and potential energy. The purpose of this project was to apply those concepts to the real world and create a functional final product. The other aspect was to represent the culture that created the design of your trebuchet, but my group divided to complete the individual aspects of the trebuchet. I took the time for construction and refinement and my group focused more on that aspect of the trebuchet.
Reflection Questions:
a) Two main energy factors influence the movement of a trebuchet projectile, it's kinetic Energy and Potential Energy. The potential energy can be determined with three of the main factors in the way a trebuchet works, the mass of the counterweight, the distance it falls, and the acceleration of gravity. This determines the potential energy of the . There are other factors though, such as the length of the arm and the angle of release. It is not at important to remember those as much as they are more constant. You will always want the release angle to be 45 degrees to get the optimal distance. The basic idea of how a trebuchet works is that the counterweight falls down, accelerating the arm up and outwards. Having a larger fall distance allows the counterweight to accelerate to higher speeds, and having a heavier counterweight puts more force on the arm. The equation for Potential energy is PE=Gravity*Fall Distance*Mass.
The other factor is what happens when the counterweight falls, the Potential Energy of the projectile is converted into kinetic energy, propelling it forwards.. The equation to get the kinetic energy of the projectile is 1/2 the mass multiplied by the velocity squared. The velocity of a projectile is the speed it has going forwards, influenced by its acceleration both positive and negative. The projectile will accelerate in the positive direction as the counterweight falls and it goes around in the sling. At the moment the projectile leaves the sling though, it loses that positive acceleration and begins to slow down. This negative acceleration decreases it's velocity over time, the force that creates this negative acceleration is gravity and air resistance. Overall, Kinetic energy is the application of potential energy to create acceleration and velocity.
b) When I did this project I definitely had to use four main 21st century skills, two of which boiling down to a lot of team work. Which are of collaboration and communication. I communicated with my group in order to make sure everything worked in the end, by making sure everyone did the best they could to provide necessary materials and to just help out in general to finish. What it means to use communication is to be able to understand what everyone in a group can do to help accomplish your shared goal. Collaboration was similar, but actually more of a second phase to communication, as using collaboration was putting what was communicated to use. Using collaboration as a group member in this project meant combining the skills and strengths of my various group members to their greatest extent to get work done.
The rest of the project really consisted of two other main 21st century skills, creativity and critical thinking. Creativity was important as I built a very unorthodox trebuchet, a floating arm trebuchet. I used creativity here by figuring out ow to build a much more complicated design than most people were building with a lot of the same parameters. To use creativity in a 21st century environment is to figure how to take other peoples ideas, and improve them or change them to fir what you need to accomplish. Critical thinking in this situation was almost the opposite. It made me step back and go, "Can I really do this" or "How can I make this idea more realistic and doable." This was definitely something that I had to use a lot of. To use critical thinking is to know your own limits in life, but to also understand that everyone makes mistakes and everything can be improved on.
c) The biggest challenge I came across in this project was getting my trebuchet to work, and unfortunately I cannot say I overcame this challenge. At the time the trebuchets were actually due mine was not complete, even though I spent a lot more time than most people on it. It was assembled on time, but not functional. I then spent every physics period and a lot of lunches refining it. This was my attempt at overcoming this challenge, and it was almost successful. By the time of the last couple of days I actually was able to get my trebuchet to fire fairly successfully a few times, actually getting a better distance than the trebuchet that one competition. The problem was that it nearly demolished itself every time it fired, and that was when it even worked. Overall I learned from this that not everything will go well in life, and even working with refinement as best as I could will not guarantee success.
d)I brought 2 main strengths to my group, and both of them helped immensely. The first was leadership skills, as I guided my group and tried my best to give everyone in my group a job to do. I was successful at this, and despite not having a working trebuchet we had one to show. If I hadn't guided my group along I don't think we would have had anything at exhibition, unless of course someone else stood up and took my place. What I did as a group leader was communicate efficiently with my group to make sure most of them had a job to do. The other strength I brought was my willingness to take some of my own time to finish it. The few times it did work were largely because of time I took at lunch to assemble and refine my trebuchet. Overall I feel that I did more than my share of work in this project and helped guide my group to not-victory-but-not-loss at the exhibition.
a) Two main energy factors influence the movement of a trebuchet projectile, it's kinetic Energy and Potential Energy. The potential energy can be determined with three of the main factors in the way a trebuchet works, the mass of the counterweight, the distance it falls, and the acceleration of gravity. This determines the potential energy of the . There are other factors though, such as the length of the arm and the angle of release. It is not at important to remember those as much as they are more constant. You will always want the release angle to be 45 degrees to get the optimal distance. The basic idea of how a trebuchet works is that the counterweight falls down, accelerating the arm up and outwards. Having a larger fall distance allows the counterweight to accelerate to higher speeds, and having a heavier counterweight puts more force on the arm. The equation for Potential energy is PE=Gravity*Fall Distance*Mass.
The other factor is what happens when the counterweight falls, the Potential Energy of the projectile is converted into kinetic energy, propelling it forwards.. The equation to get the kinetic energy of the projectile is 1/2 the mass multiplied by the velocity squared. The velocity of a projectile is the speed it has going forwards, influenced by its acceleration both positive and negative. The projectile will accelerate in the positive direction as the counterweight falls and it goes around in the sling. At the moment the projectile leaves the sling though, it loses that positive acceleration and begins to slow down. This negative acceleration decreases it's velocity over time, the force that creates this negative acceleration is gravity and air resistance. Overall, Kinetic energy is the application of potential energy to create acceleration and velocity.
b) When I did this project I definitely had to use four main 21st century skills, two of which boiling down to a lot of team work. Which are of collaboration and communication. I communicated with my group in order to make sure everything worked in the end, by making sure everyone did the best they could to provide necessary materials and to just help out in general to finish. What it means to use communication is to be able to understand what everyone in a group can do to help accomplish your shared goal. Collaboration was similar, but actually more of a second phase to communication, as using collaboration was putting what was communicated to use. Using collaboration as a group member in this project meant combining the skills and strengths of my various group members to their greatest extent to get work done.
The rest of the project really consisted of two other main 21st century skills, creativity and critical thinking. Creativity was important as I built a very unorthodox trebuchet, a floating arm trebuchet. I used creativity here by figuring out ow to build a much more complicated design than most people were building with a lot of the same parameters. To use creativity in a 21st century environment is to figure how to take other peoples ideas, and improve them or change them to fir what you need to accomplish. Critical thinking in this situation was almost the opposite. It made me step back and go, "Can I really do this" or "How can I make this idea more realistic and doable." This was definitely something that I had to use a lot of. To use critical thinking is to know your own limits in life, but to also understand that everyone makes mistakes and everything can be improved on.
c) The biggest challenge I came across in this project was getting my trebuchet to work, and unfortunately I cannot say I overcame this challenge. At the time the trebuchets were actually due mine was not complete, even though I spent a lot more time than most people on it. It was assembled on time, but not functional. I then spent every physics period and a lot of lunches refining it. This was my attempt at overcoming this challenge, and it was almost successful. By the time of the last couple of days I actually was able to get my trebuchet to fire fairly successfully a few times, actually getting a better distance than the trebuchet that one competition. The problem was that it nearly demolished itself every time it fired, and that was when it even worked. Overall I learned from this that not everything will go well in life, and even working with refinement as best as I could will not guarantee success.
d)I brought 2 main strengths to my group, and both of them helped immensely. The first was leadership skills, as I guided my group and tried my best to give everyone in my group a job to do. I was successful at this, and despite not having a working trebuchet we had one to show. If I hadn't guided my group along I don't think we would have had anything at exhibition, unless of course someone else stood up and took my place. What I did as a group leader was communicate efficiently with my group to make sure most of them had a job to do. The other strength I brought was my willingness to take some of my own time to finish it. The few times it did work were largely because of time I took at lunch to assemble and refine my trebuchet. Overall I feel that I did more than my share of work in this project and helped guide my group to not-victory-but-not-loss at the exhibition.
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