Roles
Task
HIM has created a huge problem by stealing all the food in Townsville and put it on an island far away. The Powerpuff Physicists must think really hard and find a way to bring back all the food as fast as possible before the whole town starves! Let's go girls, put our thinking caps on and let's get to it!
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Introduction
This is a very important project which is expected to take place over a long period of time. In our previous documented projects, it only lasted one or two days, so this will be a big difference. We will make a planner to divide our work and keep track of everything to be done. We have the option to choose which type of catapult to make, as catapult is only a category. We have chosen the trebuchet for we believe it will be very easy to build, operate, and control. We have goals to make our catapult appealing, stable, launch the furthest, and consistent.
With the various equations given to us based on kinematics, dynamics, energy, and momentum, we will keep them in mind for our follow up calculations for momentum, velocity, acceleration, energy, net force, range, and more.
With the various equations given to us based on kinematics, dynamics, energy, and momentum, we will keep them in mind for our follow up calculations for momentum, velocity, acceleration, energy, net force, range, and more.
Planner
First Edition
Second Edition
Final Edition
Preparation for Launch Day
Some possible questions we expect to be asked on launch day are:
On the day of our test, we have collected the following results:
As we have tested our trebuchet to calculate its ranges and where we should place the targets, we have come up with the following:
- How does your catapult work?
- How many times have you tested it?
- How much weight can it hold?
- What is your furthest range?
On the day of our test, we have collected the following results:
- 20 pounds: 12m, 12, 11
- 30 pounds: 21.5, 21.5, 20
- 50 pounds: 27.5, 23, 28
As we have tested our trebuchet to calculate its ranges and where we should place the targets, we have come up with the following:
- Target 1 (close target): 12.5 m using 24 pounds
- Target 2 (far target): 20 m using 30 pounds
- Target 3 (elevation target): 10.5 m using 22 pounds
- Target 4 (Furthest target): 30 m using all our weights (84 pounds)
Materials |
All materials were gathered from Home Depot unless we had the materials ourselves
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launch day: May 28, 2015
Observations
On the day of the launch, our catapult was very successful at hitting the target. On our first trial, our range was set to 12.5 metres. On our first trial, we hit the target successfully. On our second trial, the range was set to 20 metres. The first run was not successful as the ball did not go in the net. On our second run, the ball went into the net successfully. On our third trial, an elevation of 1.2 metres was set up. The range of this trial was 10.5 metres. The first run was unsuccessful because the ball hit the bottom net instead of the elevated one. The second trial was successful because the ball hit the elevated net.
Video Tracker
Results
Analysis
As shown above by the image under the section "Results", the catapult hit all the chosen targets. The catapult hit the first target 12.5m away and at an elevation of 0m on the first try, the second target 20m away and at an elevation of 0m on the second try and the final target 10.5 m away and at an elevation of 1.1m on the second try. For maximum range, the catapult launched the tennis ball 28m, 30.5m and 35m; resulting in an average maximum range of about 31m.
These were the results obtained because we devised a plan and constructed a catapult that a sturdy and easy to manipulate. The usage of free weights was effective and fast. To hit each individual target we knew from prior testing what dumbbells to use to obtain the correct distance and elevation to hit the target. The weights were reliable and our design for the catapult allowed the dumbbells to be easily transferred on. Also, our design allowed us to load heavy weights without any significant damage. Our design was very simple, containing only parts that were crucial to the ability of the catapult working. The simplicity of the design allowed for easy transfer. Our release mechanism was highly effective as well, as it was quick to set up and easy to use. We were able to pull the string that allowed the catapult to launch without interfering in the launch. This prevented any human errors in terms to release of the catapult for the launch. Our catapult also made the tests on testing day more convenient for us due to the special additions. Adding cups at the side of the catapults ensured we did not lose our stuff (e.g. pencils, phones, tennis ball and water bottle), so we were able to quickly set up for each run.
Some errors that possibly affected our results on testing day was the wind and bending of the copper rod running through the arm of the catapult. The strong wind blowing in from about North caused the ball to go South when we wanted it to go East. This wasn't something we had no control over and sadly we did not encounter such strong wind during pre-testing, so we had to work on the spot to fix the problem. We adjusted our catapult to face about South-East, so when the tennis ball was launched it went East. This was time consuming as we did not have time to sit down and devise a equation to figure out what way to turn the catapult to get the ball to go in the correct direction. Therefore, we had use trial and error. Luckily, we are able to work quickly as a group and become successful. Another error we faced was that at the end, when we used the maximum amount of weight we had to obtain maximum range, the copper rod supporting the arm started to bend. This did not have a major influence on our results and we did not have to do any repairs on the catapult, but certainly our catapult could have obtained a greater range. We had underestimated the capacity of our catapult, so we did not take more weight with us. If we had been more aware of its capacity, we would brought weight on test day and to prevent bending, we would have used a thicker copper rod. Overall, there were not many errors as we had tested our catapult thoroughly before test day and made adjustments. That is also why in the future we would most likely only change the thickness of the copper rod have we another chance to do this assignment again.
These were the results obtained because we devised a plan and constructed a catapult that a sturdy and easy to manipulate. The usage of free weights was effective and fast. To hit each individual target we knew from prior testing what dumbbells to use to obtain the correct distance and elevation to hit the target. The weights were reliable and our design for the catapult allowed the dumbbells to be easily transferred on. Also, our design allowed us to load heavy weights without any significant damage. Our design was very simple, containing only parts that were crucial to the ability of the catapult working. The simplicity of the design allowed for easy transfer. Our release mechanism was highly effective as well, as it was quick to set up and easy to use. We were able to pull the string that allowed the catapult to launch without interfering in the launch. This prevented any human errors in terms to release of the catapult for the launch. Our catapult also made the tests on testing day more convenient for us due to the special additions. Adding cups at the side of the catapults ensured we did not lose our stuff (e.g. pencils, phones, tennis ball and water bottle), so we were able to quickly set up for each run.
Some errors that possibly affected our results on testing day was the wind and bending of the copper rod running through the arm of the catapult. The strong wind blowing in from about North caused the ball to go South when we wanted it to go East. This wasn't something we had no control over and sadly we did not encounter such strong wind during pre-testing, so we had to work on the spot to fix the problem. We adjusted our catapult to face about South-East, so when the tennis ball was launched it went East. This was time consuming as we did not have time to sit down and devise a equation to figure out what way to turn the catapult to get the ball to go in the correct direction. Therefore, we had use trial and error. Luckily, we are able to work quickly as a group and become successful. Another error we faced was that at the end, when we used the maximum amount of weight we had to obtain maximum range, the copper rod supporting the arm started to bend. This did not have a major influence on our results and we did not have to do any repairs on the catapult, but certainly our catapult could have obtained a greater range. We had underestimated the capacity of our catapult, so we did not take more weight with us. If we had been more aware of its capacity, we would brought weight on test day and to prevent bending, we would have used a thicker copper rod. Overall, there were not many errors as we had tested our catapult thoroughly before test day and made adjustments. That is also why in the future we would most likely only change the thickness of the copper rod have we another chance to do this assignment again.
Conclusion
In conclusion, we required to build a catapult that was able to hit three targets, at least 2.0m apart and with two different elevation 1.1m apart, within 3 tries for each target. We were able successfully build a catapult that fulfilled these requirements. Our catapult hit the chosen target within less than 3 tries and obtained an average maximum range of 31m. We faced few errors during testing day as we tested and adjusted our catapult prior to this day. In summary, the errors we faced were due to the strong wind causing the tennis ball to change the direction of its pathway and bending of the copper rod supporting the arm of the catapult. We concluded that there was nothing we could have done to minimize the effects of the wind, expect change the direction that the catapult launched the ball in such as a way that we got the tennis ball to hit the targets. To have prevent bending of the rod, we should have used a thicker copper rod. In future studies, we could complete the same assignment while trying to fulfill the same requirements but using a different type of catapult to be able to explore the characteristics of that type of catapult.
Evalutions
Group:
Catapults, another assignment well-done by the powerful physicists. We could not be more proud of ourselves at this moment. At the start of this assignment, we were nervous. We did not think we possessed the right skills and knowledge in terms of construction to be as successful as we wished to be in this task. Despite that, we were ready to give in more than we possessed. This attitude and dedication is the reason we were as successful as we were. During construction, we all stepped outside of our comfort zone and aided in building of the catapult. We were serious about our task and did not sit around, allowing a parent to build our project for us. This is precisely the reason why we are so happy with the outcome of this assignment. We created our own design and build our own catapult with minimum assistance! Having little knowledge about construction but a worthy amount of knowledge about physics, we were able to construct a catapult that successfully met all the requirements! When we hit all the targets, we were shocked. We had tested our catapult a numerous amount of times and we knew our catapult had the capacity to hit each target that we had chosen, but to see this actually happening on testing day was amazing. Our happiness was uncontainable. We're glad that we did not treat any component of this assignment with less value than the other parts. We directed a trailer for our catapult that not only shocked Mr. Peasley but also shocked our classmates with our talents and creativity. We made our assignment enjoyable by adding our creativity and strengths into each part to be successful. For instance, we choose to make a trailer over a commercial because that's where our strengths laid as a group. Lauren is amazing with editing, Ravneet is a dramatist and Sanaa is highly creative. Put all that together and you end up with a trailer that blows everyone out of the water. As cheesy as this might sound, we'd like to end of by saying that we're thankful that this project gave us more confidence in ourselves. As we've said before, we never thought we could build such an amazing catapult and to have shocked ourselves by doing so has been one of the best experiences in grade 12 physics.
Lauren:
Throughout this semester, the catapult project has been my favourite. This is because it was a working progress, we had a fun original movie trailer to film, we had a mini field trip, and our trebuchet was very successful and consistent throughout. Overall I believe that with the previous skills that our group has used for the past projects, we excelled very well in this particular one. We had to keep constant and good communication to make sure everything was done to the best of our abilities and we were all responsible, making sure the others knew when we were available and used our problem-solving skills to overcome obstacles. I was very pleased on the day of our launch because even after coming back from the strike, we were still very prepared for anything. Our results were incredible because we either hit the target on the first or second trial and were not in need of a third. Overall, this has been one of the most exciting projects I have ever done and I am glad to have completed it successfully with my group members.
Ravneet:
So far this course, constructing a catapult was my favourite task. Last semester I was still considering whether or not to take physics and seeing other students build these amazing, difficult-looking catapults almost scared me into not taking grade 12 physics. I'm so glad I did not drop physics. Although building a catapult was no walk in the park and extremely time-consuming, it was interesting. And most importantly, it was a project that at the end of it I felt immensely proud of myself. I loved how seamlessly my group was able to work together from devising a design to constructing the catapult without any arguments. Everyone gave in their best effort and was always there to help. No matter what someone schedule was, we were able to meet up and work to meet every deadline. I had a lot of fun throughout the assignment, especially creating our own trailer for the catapult as we were working inside our comfort zone. This allowed for everyone to excel in their area of strength. After this project, I am even more glad that I choose this group to work with at the start of this semester. I know for sure that I could not have chosen a better group. Finally, I was EXTREMELY happy to have showed some classmates that my group of all girls was "able" to build, in my opinion, the best catapult in our class. :)
Sanaa:
The catapult project has been my favourite assignment in physics this semester. I absolutely loved the process of it, from the brainstorming, design, to the construction and launching of the catapult. Throughout this project, I have had many responsibilities in order to make our project successful. I was very much involved in the design process where I used my creativity skills to design a reliable design for our catapult. While building the catapult, I brought in wood and many other materials and so did my group members. While building the catapult, I had so much fun with my group members. We were always focused and were always optimistic when something would go wrong. We would always be there when it was needed except for one day when I couldn’t make it for the testing of the catapult, so my group members did it without me. While filming for the trailer, I also had a lot fun. With all the anticipation for the launch day, it finally arrived on May 28th 2015. On the launch day, my group and I did such a good job with organization and just being involved with everything. Our launches were all successful, and we were the only group who had not gone to the third run of a trial. We felt really happy about that! Overall this was a lot of fun.