Above is a proof of efficacy document for the trebuchet my group designed and built. The description and performance are listed as well.
Our next project was an alternative energy vehilce. The goal of this project was to move 2 passengers ( 2 rolls of pennies weighing 2.5 grams) 5 meters. Our group having 4 members decided to try two different vehicles, one powered by gravity and another powered by magnets. Both were very complex to build and required a lot of attention to detail. While building the cars we ran into many struggles, starting with the gravity powered vehicles, we needed enough force to overcome the downwards for of the car on the ground.We tried increasing the traction of the wheels and increasing the weight pulling down to rotate the axle. We did not prevail. And our magnetic powered vehicle was very hard to balance the magnets to get the car to levitate. We then tried to modify both to work however our efforts we not good enough. To simplify our building we went to the basics. We made a small box just big enough to house the two rolls of pennies. Next we attached two wheels from an R.C car to stay rigid with the body. This mean as the wheels roll, so did the body of the car. We made modified seat belts and attached weights to one side of the car. This allowed the car to roll unevenly and eventually come to a stop at 5 meters. We rolled it down a ramp 35 m from the base and it went exactly 5 meters. We tested consistency and we felt confident. As we ran the car more the wheels would become more loose. Tightening them ended up making one screw very loose with no time to fix it. At our presentation we only achieved 4 meters due to one wheel being uneven. We learned that we should have made more modifications to ensure consistency.
Overview/What I learned: I learned that self sacrifice is important for the betterment of the group even if it meant sacrificing the little free time I have to help produce a better outcome for everyone. Also everyone learned that time management was key while creating our presentations. If we had planned better than our slides would be more accurate and full of more key rich information. We rushed through it and we did not produce the best slide show and presentation that we could have.
Content:
Distance vs Time: The measurement of distance vs time is known as either velocity or speed or the amount of distance you can cover in a set amount of time.
Velocity: Velocity is the comparison of distance and time in a certain and pronounced direction. There are many components of velocity. These include vertical, horizontal, and total velocity is also included. Vertical velocity is at the rate and object flies or falls. Next the horizontal component, this is how fast an object travels away from the starting point. Next the total velocity, this can be calculated when you know both velocities and then you can solve for the total velocity of a ball flying with an arc flight path.
Gravitational potential energy: The amount of potential energy in and object due to the amount of gravity acting on it and its force on the object.
Kinetic Energy: The energy in an object while it is in motion.
Thermal energy: Energy in the form of heat. This plays a key role in the conservation of energy as friction creates thermal energy and heat takes away from the kinetic energy in an object which causes the vehicle to stop and all of the energy to be conserved.
Friction: The rubbing of molecules that creates thermal energy and takes away kinetic energy and slows an object down.