During break we finished the top truss structure of our bridge. We used a warren truss system for the top of our bridge. We also have doubled up the road portion of our bridge for even more stability. Now we aren’t sure whether to build a bottom truss. We still will double up our upper truss and further stabilize it across but after that we should be done
Today we have started building the top of the truss system wee are starting to see if we will have enough wood to build a top and bottom truss system. The glue is also a problem because we can’t use the gusses until we have built the top of the truss. It has to stay stable until then which means we have to be gentle. We are using notch joints in the deck to stabilize the truss and we are going to put a “fencing” on the outside of the truss to stabilize it even more.
Podcast number 2
Today we have decided to completely change our bridge design. We have decided to make a bridge with two truss systems one on top and one on bottom. In the end we decided that it would be to difficult and risky to do a curved piece of wood. We have drawn a model to scale and are ready to start cutting and building .
It is the second day of building the bridge and iwantaprize is getting close to a final bridge design. We are thinking about having a strait piece of wood on top of a warren truss with an arch under the truss. The tricky part is connecting the bridge to the test system and we will try to measure it exactly to fit right in the tester. But we may leave a little room so we can wedge wood between the walls so it will fit. Opposed to making it to big and then it won’t fit and we will be disqualified .
First podcast
Today we drafted Eddie and stared to begin our bridge concepts. We got all of our wood started thinking of ideas . We feel that we want to to put an arch but the difficultly increases as the strength increases. We will have to treat the wood so it will stay bent and measure it out perfectly. We have a basic design now and are beginning to scale out the crucial parts.
Potential energy and Kinetic energy’s sum are equal to the total energy. Tis means when the roller coaster is at the top its KE equal zero and its PE equals the total energy. When the roller coaster is at the bottom of the slope it has zero PE and all of the energy is changed in to KE and it also equals the total energy
Today we went over some homework problems and started learning about machines. A Machine is a device for increasing force. It also can change the direction of the force. Work input = work output. W=E=KE=PE. After those notes we took a quiz which i completely AC’ED. (y) Go Gaels
luke good job on the quiz. we also learned that no machine has 100 percent efficiency that is why we can use the formula AMA/IMA x 100 to find the efficiency.
Efficiency = Work output/ Work input. No machine has 100 percent efficiency. Efficiency also = AMA/ IMA. x 100
Work=change in energy=Change in KE =change in PE.
