Our third project at STEM Marin, was to create a hybrid (actually alternative energy) car. However, the car had to go an exact 5 meter distance, no more, no less. In order to accomplish this goal, we had to create a type of "engine" that stored potential energy in any form. We chose potential energy in the form of spring potential energy from a rat trap arm. Seen below is our presentation to car executives explaining how our car works and its key selling points.
In the building of our car, we learned and reinforced or knowledge of the concepts listed below in the order as seen in out presentation.
Potential energy (PE) - is energy due to the position of an object. There are two types of potential energy, gravitational potential energy and elastic potential energy. If an object is suspended in air 2 meters above the ground, it has gravitational potential energy. Gravitational potential energy due to gravity is measured by multiplying the mass of an object by the height of an object by the acceleration of the object due to gravity and is measured in Joules (J). If an object has energy due to the deformation/stretching of an elastic substance, it has elastic potential energy. It is calculated by multiplying the force of the elastic substance by the distance it is stretched. In our car, we found the potential energy of our rat trap to be about 8.66 Joules.
Kinetic Energy (KE) - is energy due to motion of an object. If an object is in motion, it has kinetic energy. Kinetic Energy is measured in Joules (J). In our car, we found that at its maximum kinetic energy, it had about 1.27 Joules of kinetic energy.
Thermal Energy (TE) - is energy lost in the transfer of potential to kinetic energy. Thermal Energy is measured in Joules (J). Our car stopped when all potential energy and kinetic energy were transferred into thermal energy.
Velocity (V) - is speed in a given direction. To find speed, you divide the distance (D) an object traveled by the time (T) it took the object to travel to that distance, so we find velocity using the same procedure. The unit of velocity is meters per second (m/s). Our car's velocity increased until it peaked and started losing velocity until it stopped.
Acceleration (A) - is the rate velocity changes over time. Acceleration is measured in meters per second squared (m/s^2)In falling objects, acceleration is equal to gravity (9.8 m/s^2). Our car accelerated when started and started to decelerate until it eventually stopped.
Potential energy (PE) - is energy due to the position of an object. There are two types of potential energy, gravitational potential energy and elastic potential energy. If an object is suspended in air 2 meters above the ground, it has gravitational potential energy. Gravitational potential energy due to gravity is measured by multiplying the mass of an object by the height of an object by the acceleration of the object due to gravity and is measured in Joules (J). If an object has energy due to the deformation/stretching of an elastic substance, it has elastic potential energy. It is calculated by multiplying the force of the elastic substance by the distance it is stretched. In our car, we found the potential energy of our rat trap to be about 8.66 Joules.
Kinetic Energy (KE) - is energy due to motion of an object. If an object is in motion, it has kinetic energy. Kinetic Energy is measured in Joules (J). In our car, we found that at its maximum kinetic energy, it had about 1.27 Joules of kinetic energy.
Thermal Energy (TE) - is energy lost in the transfer of potential to kinetic energy. Thermal Energy is measured in Joules (J). Our car stopped when all potential energy and kinetic energy were transferred into thermal energy.
Velocity (V) - is speed in a given direction. To find speed, you divide the distance (D) an object traveled by the time (T) it took the object to travel to that distance, so we find velocity using the same procedure. The unit of velocity is meters per second (m/s). Our car's velocity increased until it peaked and started losing velocity until it stopped.
Acceleration (A) - is the rate velocity changes over time. Acceleration is measured in meters per second squared (m/s^2)In falling objects, acceleration is equal to gravity (9.8 m/s^2). Our car accelerated when started and started to decelerate until it eventually stopped.
Although our particular group took a simplistic approach to the project, I had a good time working on our car and helping other groups with their cars. Across the way, there were successful moments and some not so successful moments. Starting with the good, I noticed that by taking such a simple method of powering our car, we shrunk our build time. We ended up having a working model by our second day so we had lots of time to make adjustments and fine-tune our car to go the exact distance required. We also managed our time very well and had our project completed early which allowed us to help some other groups who were not so time efficient. For this particular project, our group did not have very many unsuccessful moments. The only issues we ran into was with bringing in a laptop to make our movie on and to divide the group work evenly, however we solved both of those by just communicating with each other openly.
Even though our project came out great, I still feel like I need to work on stepping back and letting others lead. I think I ended up leading the project when we all should have been on the same level. I also think I need to work on being prepared at all times. I found that at a few times in the project, we had finished our work early and couldn't proceed ahead because of lack of necessary resources.
As a person, I learned that I need to communicate more openly and not be shy when diving group work. I found that when I actually voiced my thoughts, everything went very smoothly and worked well. I also learned to try to be as helpful to other groups as I can be. I found that it was very fun and rewarding to help other groups accomplish their goals.
Overall, I found this project to be a unique and interesting way to learn about energy, velocity, acceleration, and more.
Even though our project came out great, I still feel like I need to work on stepping back and letting others lead. I think I ended up leading the project when we all should have been on the same level. I also think I need to work on being prepared at all times. I found that at a few times in the project, we had finished our work early and couldn't proceed ahead because of lack of necessary resources.
As a person, I learned that I need to communicate more openly and not be shy when diving group work. I found that when I actually voiced my thoughts, everything went very smoothly and worked well. I also learned to try to be as helpful to other groups as I can be. I found that it was very fun and rewarding to help other groups accomplish their goals.
Overall, I found this project to be a unique and interesting way to learn about energy, velocity, acceleration, and more.