Project Description
As a group, we were to design an environmentally friendly car powered by any type of potential energy, except for chemical and nuclear, where the energy cannot be stored, and must be used directly, for the Hyundai Company. The car must also be self-propelled and be able to mark as close to 5 meters as possible, while carrying a load of 250g. In addition to creating a design that fulfills the aforementioned criteria, a short sales pitch was also included to present the concept of the prototype.
Key Concepts and TermsDistance (d): Amount of space between two points, measured in meters, m.
Time (t): Progress of events, measured in seconds, s. Mass (m): The amount of matter and weight of atoms in an object, measured in Kilograms (Kg). Height (h): The vertical distance either between the top and bottom of something or between a base and something above it, measured in meters (m). Force (F): The intensity of body or system, producing or tending to produce a change in movement or in shape or other effects. (A push or pull on an object). Acceleration (a): the rate of change of velocity per unit of time, measured in m/s². Acceleration Due to Gravity (g or a sub g): Gravity is a force between two objects, directly proportional (~) to their mass and the distance between them. The gravitational constant is 9.8 m/s². Velocity(v): Rate of distance travelled in a direction, a vector quantity measured in meters/second or m/s and direction. v=d/t Kinetic Energy (KE): energy that a body possesses by virtue of being in motion, measured in Joules (J). W=PE=KE KE= 1/2*mv² Gravitational Potential Energy (PE sub g): Energy an object has due to position at a height in a gravitational field, measured in Joules (J). W=PE=KE PE=mgh The Law of Conservation of Energy: The total energy of an isolated system remains constant, as energy cannot be created or destroyed, but rather transformed from one form to another. Additional ConceptsSpring Constant (Resistance) (k): Measure of how difficult it is to expand or compress the spring. Measured in N/m
F=kd k=F/d Potential Energy of the Spring/ Elastic Potential Energy (PE sub spring): The energy stored in a spring when it is compressed or expanded. Measured In Joules. Elastic PE= 1/2*kx²; x= distance spring is compressed or expanded. |
Graphs ExplainedDistance vs. Time (Slide 9)
From meter to meter, the graph's slope is getting steeper and steeper. This shows the general trend of an exponential amount of distance being covered over a period of time. Since exponential graphs increase their y-values along more than the previous, per x-value and the slope of the distance covered increases per x- value. There is a exponentially positive trend between the distance covered in the same amount of time. Energy vs. Time (Slide 10): The Total Energy was calculated by finding the Potential Energy of the system. Since PE=mgh, then PE=1.26kg*9.8m/s² * (height of mass drop, in meters), in this case 0.58m. And because the Total Energy is the same as all the initial energy of the car, or the Potential Energy, Then Total Energy~7.1J. The reason why the Total Energy is the same is because of the Law of Conservation of Energy. This represents a constant amount of energy in the system, that is not created or destroyed, but changed into various forms, like Potential, Kinetic or Thermal Energy. Kinetic Energy was calculated by using KE= 1/2*mv². The mass used for this calculation was the mass of the whole vehicle, and the velocities it traveled as a sum per meter. The Thermal Energy was calculated by subtracting the Total Energy from the Potential Energy from the Kinetic Energy. Our vehicles efficiency is 14%, as the change in Potential Energy is about 1 Joule per meter and the Total Energy was about 7 Joules. So 1/7~14% energy efficiency of the car. |
The Presentation
Reflection
Before the project had even begun, I didn't know what to expect of the productivity of our group. Fortunately, much thanks to Owen Ondricek and Jackson Hilton, this project had gone very smoothly, without many major problems. We had found ourselves to be very productive, and focused on our work. Everything from blueprinting, to construction, to testing, to the powerpoint was surprisingly evenly delegated among our group. With this, the flexibility of our teammates made it even easier to complete this project. We had come up with a simple design: a pulley, an axle, a mass, string, and CDs, and when engineering, simplistic solutions can become one of the most effective solutions. I was proud that our blueprint changed minimally, and our design had gone the 5 meters exactly. But even with such a great group, we did have our pitfalls. Originally, we had used wooden wheels, but the most glaring problem with this idea was making sure that the whole circumference of the wheel were equidistant from the center. After learning that cutting wood into perfect wheels is a very demanding task, we had opted for DVDs, 3 per side of the axles. We knew that this would provide the strength, and smooth curvature that we needed for our wheels. Another component I would like to refine would be keeping the axles in place, so they do not turn and move forward. Another issue we had run into was time management. I felt as though we had spent too much of our focus on retesting a reliable car that could meet the 5 meter specification, with the 250g load. We could have better spent this time on creating our Google Slides presentation. If we had chose to prioritize the slideshow as opposed to making sure the car works, we could have been more prepared for the presentation. With this group, they let me realize the importance of cooperation and trust, because without this, the workload and flexibility would not have been present to this degree. Overall I am very pleased with the work I have contributed towards the group's success, and the people within the group who did the same.
-Nihal Nazeem
-Nihal Nazeem