The objective of this project was to utilize our knowledge from physics class to construct the best possible car that would go up the hill by maximizing potential/kinetic energy. We were also trying to accomplish building a car that would go up the hill quickly and smoothly. Overall, our main objective was to win the entire competition with the car.
NG 2 - Investigating
Our plan was altered from our original design, so our entire Car Plan was changed. that happens! We found that making the car out of a single rat trap was the most efficient way to build the best car possible within the $20 budget. In order to construct the vehicle, the base was to be made from the rat trap itself. Then, we place two eye hooks on each side of the rat trap so that there would be spots to attach the axels to the car. Next, we used a power saw to split one wooden dowel in half. These dowels served as the axels, which we slipped into the eye hooks. We also cut the straw into four, 1-inch long pieces and placed them on the outside of the eye hooks right before attaching the wheels. Wooden plaques were then used as said wheels, which were also drilled into used a drill so that each one would fit on the sides of the rat trap. We used tacky glue to secure them into place and then waited for them to dry. Afterwords, we put two rubber bands on each wheel for a total of 8 rubber bands to utilize friction. Lastly, we used a parachute cord and tied it to the spring of the rat trap, which thus served as our winder. A nail was then placed into the back axel to hold the cord in place as we winded up the wheels.
| Material | Cost |
|---|---|
| Rat Trap (x1) | $1.97 |
| Wooden Dowels 28 cm (x10 bag) | $3.00 |
| Rubber bands (assorted bag) | $2.50 |
| Parachute cord (x1) | Free |
| Nail (x1) | Free |
| Wooden plaques (x4) | $6.00 |
| Eye hooks 2 in (x4) | $3.99 |
| Straw | Free |
| TOTAL | $17.46 |
NG 3 - Analysis
Race 1: The first race we competed in was in the 32 round since we got a bye for the first round. In this round, the opponent's car was kind of weak so we easily crushed their car. It wasn't a surprise since I had seen it in action in the round before, so I knew that our car would be faster than the other one.good
Race 2: This race was more competitive, however the opponent's car had a lighter body than ours, so although we both met at the top of the hill at the same time, our car was able to push their car back down with ease.
Race 3: This race was our last race before getting eliminated. Both cars performed pretty well considering that they had made it far into the competition. I'm biased in thinking that my partner and I got a bad break. In the race, our car and the opponent's car met at the top of the hill at the same time, but his car was heavier than mine, therefore my car slide on top of his. We were still at the same position though, so neither had the advantage of securing the hill. However, it was ruled that his car pushed mine even though we went up at the same time. I thought it was unfair initially, but I guess it didn't really matter since it was a fun competition in the end. My only regret was that my car wasn't heavy enough to push my opponent's car instead of the other way around.
NG 4 - Developing a Model
The entire model of our car is completely different from the original model that I posted in the Justification Statement. The final design was changed so that instead of being dependent on two mouse traps, one giant rat trap would be used. And instead of using wooden sticks as a lever to unwind the back axel, the actual spring itself was used to unwind it. Not only did this save space so that we would meet the 30 cm maximum length, but it also made it more convenient so that during the competition, the only thing we would have to really prepare would have just been the spring. Overall, I think that our new model was sleeker and more durable than our old one. yes
NG 5 - Evidence
To some extent, we were successful. We were successful because we achieved our goal of building a great car using materials under a $20 budget. However, we were unsuccessful because we did not achieve our goal of winning the whole competition. I think that this project did a good job of reminding us about the relationship between friction and kinetic energy, as well as forces in general. It also reminded us about Newton's three laws of motion, especially the 1st and 2nd laws. The concept of inertia and acceleration were keys to being successful in the competition. I think that the winner's car was the evidence that showed this. Patrick's car was a beast because he applied what he remembered about forces and momentum (and weights) into designing a perfect car that balanced all of these ideas. His was heavy enough so that it knocked back lighter cars, but was light enough so that the energy from the spring of the rat trap moved it and accelerated it with ease. If I were to do this again, I would add more weights to my car. I think that this was the biggest obstacle coming in to the Sweet 16 round. Every car was durable enough to show why Newton's Third Law would be why they would destroy anything lighter than their own cars. Equal forces but unequal masses the main thing that I would want to address if we did this again. good job!
