Alternative Energy Vehicle/Fire Away!
We were given 5 weeks to complete two projects. One was a catapult that was able to launch a projectile as far as possible and an alternative energy vehicle that can carry 2 rolls of pennies a total of 5 meters safely and coming up with a way to create energy for it. We spent the majority of the time in the maker-space creating our projects and then bringing them either outside or in the classroom for testing and analysis.
First was our catapult/trebuchet, we spent about 2 weeks on this project, we spent most of this project in the maker-space. First we built our first catapult prototype based of of the examples in class. Then we tested our prototype out and tried to launch a projectile as far as we could. Then, each group chose a modification to make to their catapult, ours was pullback distance, and present it on a poster. After this we implemented these modifications into our design in hope that it would increase the distance. After our catapult was finished with the modifications and done being built then we took data on our catapult and put it into a "Proof of Efficacy Document"
Our next project was the Alternative Energy Vehicle, this project we spent around 3 weeks on this project. Our first 3 days were in the maker-space. We had to make a vehicle that ran 5 meters exact, no more or no less. We never did make it perfectly but our car did stop around 5.25 meters. After our car was built then we brought it into the classroom for testing and data collecting. We then made some key modifications to make our car run smoother and go the full 5 meters. Our most important change was using rubber bands around the edge of our cd's to add grip to them. After this we made a bunch of performance graphs and put them into a presentation. We then presented them to our class and this was our final.
Content:
Spring Potential Energy: the energy stored in the stretch or compression of an object (PEspring = 1/2 kx²)
Vehicle - Stretch in our rubber bands, there was a spring potential energy of 3.49 J at the beginning, 2.13 J at 1m, 1.1 J at 2m and 0 for the rest of the run.
Catapult - Stretch in our rubber bands 31.25 J
Gravitational Potential Energy: the energy an object has due due to its height or position in a gravitational field (PEg = mgh)
Kinetic Energy: the energy due to motion (KE = 1/2 mv²)
Vehicle - Kinetic energy of our vehicle was 0 J at the beginning, 0.4 J at 1m, 0.53 J at 2m, 0.4 J at 3m, 0.17 J at 4m, and 0.04 at 5m.
Catapult - The kinetic energy of our projectile was 1.82 J
Total Energy: The addition of all the energies (Total E = TE + KE + PE)
Vehicle - The total energy for our vehicle was 3.49 J.
Thermal Energy: the amount of energy lost to heat (TE = Total E - PE - KE)
Vehicle - The thermal energy was 0 J at the beginning, 0.95 J at 1m, 1.83 J at 2m, 3.08 J at 3m, 3.31 J at 4m, 3.44 J at 5m, and 3.49 J at 5.25m.
Rotational Inertia: An object's resistance to changing its rotational state.
Reflection:
I felt like the workload wasn't very well divided with our group. I found myself socializing with other groups often during the calculations portion of our projects. I also felt like I didn't take charge in my group enough. I let my group do a lot of the building of our alternative energy vehicle. I asked to help, but it is hard for 3 people to be working on a tiny car together all at once. But I feel like I was very good at communicating with my group on what needs to get done and what everyone should be doing. I was also very open minded and listened to my group members ideas and tried to implement them into our design best that I could. Overall I was very happy with myself and how I did on these projects and know what I can improve on for our next project.