Key Question:
Basically our objective was to build a self-propelled car with a rat trap or any other sort of creative method. The primary goal of this was to get the car up and over the hill. As long as you did that, you got a grade. But to add more fire to the fuel, the stakes were made a little hire. Not only were you suppose to get your car to go over the hill but you would also be facing other opponents. And essentially the best car was the last one standing or the "King of the Hill". The car that made it to the top of the hill was the winner.
Investigating:
Rat Trap
We will make a car that is medium in length with a rat trap to propel it. We used small wooden wheels in both the front and back, with weights in the back to keep the friction between the wheels and ground. To add more friction to the wheels we put balloons and rubber bands on it, so that it didn't go to fast. We then attached a string to the spring and the axel. We then torqued it and spun it until we couldn't anymore. We would then release the rat trap causing the string to pull on the axel and spin the wheels. This enabled the rat trap to go up the hill at a high velocity.
Materials List: Our rat trap will be 15cm x 10cm
- rat trap- $2.50
- cardboard tube- .25 cents
- rubber bands- .10 cents
- string- .20 cents
- plastic rods- $1.00
- washers- $1.00
- balloons- $1.00
Analysis:
first round: We got a first round bye because the judges believed we had one of the top cars in our class. We were very pleased.
Round of 64: In the round of 64, our opponents car was a lot smaller and slower than ours. What made our car so good is that it got to the top quicker than most cars. We easily won this race knocking the car completely backwards, almost causing it to fall off.good
Round of 32: Next was the round of the 32. It was not that much harder. However, this time the opponents car was almost the exact same size as our car. We came out with a victory. This is because our car made it up the hill quicker than the other. We were extremely pleased and started to think we could make it to at least the sweet sixteen. Our car had easily defeated our opponents.
round of 16: This was not the best round for us. We lost this round. It was devastating because our car was better than our opponents. We should not have lost. But when we released our car, the hand got slightly stuck causing the car to be slower than usual. We should not have lost. We lost because our hand got in the way. bummer!!!!
To be honest, I thought our car was at least an elite eight car. I did too! If it wasn't for that small mistake, I believe our car could have made it to the final... maybe even won it all. However, we didn't and thats just life. We were extremely pleased with our car. It turned out to work a lot better than we had expected it to. We did not think that it would get up the hill as fast as it did. It felt good to create something that worked extremely well and almost carried us to victory if not for a minor error. Besides that small error, we were extremely pleased with this project and recommend it to others. good!
Developing Model:
We are making a car with a light frame and a rat trap to give it a lot of power. There are four forces acting on our car: normal force, force of gravity, force of push, and friction force. We added weights on the back so that gravity keeps friction between the wheels and the ground. The balloons and rubber bands will also create friction with the ramp. Our car had a large acceleration at the beginning hoping that it will be fast enough to reach the top of the hill. Our car will accelerate and have the highest velocity at the base of the ramp and decrease as it goes towards the top. Incorporating Newtons laws, our car demonstrates Newton's 1st law which is "A body in motion will stay in motion unless an outside force acts upon it and a body at rest will stay at rest unless an outside force acts upon it." The rat trap car will stay in motion until the trigger bar runs out of string to pull. Plus, the car will slow from friction. Our rat trap also demonstrates Newton's 3rd law of motion which is "For every action there is an equal but opposite reaction." In this case when the trap is set off (action) the car propels (reaction). The opposite reaction is that the car propels forward starting from being still to its opposite movement which is moving. This speed combined with the medium mass of the car should enable our car to easily make it up the hill. Although our opponent may be stronger and have more mass we can still successfully beat theme by beating them up the hill. Lastly, there will be a change in momentum in our car when it hits our opponents car. The car with the greater mass, velocity, and momentum will win the battle. This speed combined with the medium mass of the car will create enough momentum to destroy any car on the track.
Yes, I do believe we were extremely successful. To be honest, I had a lot of doubt coming into this project because I didn't believe we could build a good car.why not? However, we were able to complete a really successful car. We were successful because we built a car that successfully could go up a hill. We were able to get the right materials and successfully build a car that could not only go up a ramp but also defeat other opponents. I believe were most successful because of our velocity. Our car did not weigh to much and we had really strong wheels with the perfect amount of friction. This enabled our car to be the first one up the hill almost every time. Its large acceleration at the beginning was key and its medium weight helped stop other strong cars. Our car just had more momentum and a higher velocity. However, there were some cars that stood out more than others. The cars that were the most successful used some type of really strong string or bungy chord to push it up the hill. What also helped cars reach the later stages was some sort of ramp attached to the front of the car. I thought that was extremely interesting. If i was to do this project again, i probably would not change my car up to much. The only thing I might do is add a little ramp to the front of my car and use some type of flexible chord or bunny chord. Other than that, I believed my car could have won it all. If it wasn't for that minor mistake of getting the hand stuck, I believe we could have won it all.
No comments:
Post a Comment