Project 1
This project of making a car go and stop exactly at five meters was at times challenging and also at times easy going. The challenging stuff was coming up with an origanal idea and then going to make it work. Well our first idea was to make a fan powered car and we all were a huge fan of the idea. (get the pun) Anyway we built the car with a very then peice of hard wood as a base and pvc as the exels holders. Our axels were to 1/2in sticks of would that we sanded down to get minamal friction. We then attacked our weels wrapping papper around the axel to make cds fit nice and snug and also small wooden square holders, that helped to hold the cd up.
Now for the tricky part, the fan. I was the one that ended up building the fan that sadly, didn't work. I made the fan by cutting a cd into 3 slices, like a mucular sighn. I then did it again but with bigger wedges so the fan would be bigger. After that I had to glue it into yet another wodden stick that was held up by a pvc. Now to test it, we attacked a rubber band, wound it up and let go. Nothing happened. Due to the way we rounded it up, it didn't have enough tension to turn the fan. So me being the smart one that I am said to just reposition the rubber band. It worked!!! For a full foot, which wasn't five meters so we then had to think of a new power source.
Now for the tricky part, the fan. I was the one that ended up building the fan that sadly, didn't work. I made the fan by cutting a cd into 3 slices, like a mucular sighn. I then did it again but with bigger wedges so the fan would be bigger. After that I had to glue it into yet another wodden stick that was held up by a pvc. Now to test it, we attacked a rubber band, wound it up and let go. Nothing happened. Due to the way we rounded it up, it didn't have enough tension to turn the fan. So me being the smart one that I am said to just reposition the rubber band. It worked!!! For a full foot, which wasn't five meters so we then had to think of a new power source.
Project 2
Since we were already far into our building time for the car, we decided to just stick with the same car and just take off the fan. So we took off the fan and used a long rubber band as a new power source. We put a small screw through one of the axles to hold the rubber band and made it so the rubber band could fall off so we didn't have to wind it up as much. In the end, we only had to wind it up five and 1/2 times to make it go five meters. Our car was also almost 50% efficient, which is really good considering the next closest group was 17% efficient.
When building our car, we found that it had PE, KE, Thermal Energy, and a velocity. PE in Potential Energy, so the amount of energy something has before it is used. Like with a rubber band when it is streched out, it has PE. KE or Kenetic Energy is how much energy a moving object has right before it hits something. So right before a car hits a tree its going to inpact the tree with a lot of energy. Thermal energy is how much energy was lost to heat and friction. So when a wheel spins, it creats friction with the ground loosing some of the energy it orignaly had to thormal energy.
When building our car, we found that it had PE, KE, Thermal Energy, and a velocity. PE in Potential Energy, so the amount of energy something has before it is used. Like with a rubber band when it is streched out, it has PE. KE or Kenetic Energy is how much energy a moving object has right before it hits something. So right before a car hits a tree its going to inpact the tree with a lot of energy. Thermal energy is how much energy was lost to heat and friction. So when a wheel spins, it creats friction with the ground loosing some of the energy it orignaly had to thormal energy.
Presentation
When we presented, we didn't want to do a power point like everyone else, we wanted to once again try to be original. So we displayed our car and past out our blueprints and calculations to the class. We were the only ones that did this and it went really well. The only thing that could have gone better was me not counting right on the number of winds I did before I let the car go. So I got another try and got it right on the mark. Still would have been better to do it the first time but it did give us a laugh.
Reflection
Looking back on this car project, it was pretty tiering testing the car to make it go five meters over and over again. But, I would not have changed a thing on how it turned out. You might be wondering, why not make the fan idea work, and I would. I probably would have just asked my group to help me make another car so we could make our first idea work. Besides that, it was a very fun and compelling project.