My first project in STEM San Marin was building a Rube Goldberg Machine. A Rube Goldberg Machine is a machine that performs a simple task in a complicated way. The requirements for the machine were to have at least ten steps, include five simple machines, create a schematic, and find the physics behind the machine.
Our machine consists of ten steps. The first step a marble rolling down a yellow inclined plane. The second step is the marble hitting and tilting the blue lever, which causes the marble to roll down the white inclined plane. The marble rolling down the white inclined plane and hitting the second marble is the third step. The marble then rolls down the screw and is deposited into the pulley system, which is the fourth step. The fifth step is when the pulley triggers the purple lever to tilt, causing the third marble to roll down the green inclined plane. The sixth step is the marble rolling down the green inclined plane and onto the hot pink inclined plane. The seventh step is the marble rolling down the hot pink inclined plane. After this, the marble rolls down an incline plane with pipes attached to it. When the marble hits the pipes, it will make a clinking sound. This is the eighth step. The ninth step is the marble rolling down the pink inlined plane, heading towards the final step. The last step is when the marble hits the wedge, which then falls and pops the balloon.
There were many obstacles my group had to overcome during this project. For example, we had trouble figuring out where to place the screw. At first we drilled the holes too close together, which made it so that the marble stopped halfway down the screw. Another difficulty was when not having enough space on the piece of wood we built our machine on. We accidentally designed the machine so that all the steps were on the left side of the board. To fix this error, we had to move the first four steps to the right side of the board. This gave us enough space to continue building.
Calculations
Concepts
Force: A push or pull on an object, measured in Newtons (N). We calculated force in step five, which was 0.82N.
Velocity/Speed: Speed is the rate at which something moves. Velocity is the rate at which distance changes over time, both are measured in meters per second (m/s). In step eight, we found the velocity of the marble rolling down the inclined plane, which was 1.6m/s.
Kinetic Energy: Energy due to motion, measured in Joules (J). In step two, we found the kinetic energy of the marble rolling down the lever, which was 0.0017J.
Potential Energy: The stored energy of an object due to it's position, measured in Joules (J). We found the potential energy of the marble in step seven, which was 0.151J.
Acceleration: The rate of change of velocity of an object, measured in meters per second squared (m/s^2). We found the acceleration of the marble rolling down the inclined plane in step three. The acceleration was 5.47m/^2. Mechanical Advantage: How much easier something is because of a tool. In step five, we found the mechanical advantage of the lever, which was 5.
Reflection
Building a Rube Goldberg Machine was a great way to start off the year at STEM Marin. This project was a fun challenge that taught me many facts and things about myself. During this project, I learned that I need to do a better job keeping my group on track and making sure they are working. My group would get off task quite often, causing us to be behind on completing our project and forcing people to do more work than others. One way to help fix this problem is by keeping the conversations project-related. If a group member starts to distract other members, then I should redirect the member to helping work on the project or assigning them something to work on. A second problem my group had was time management. Since my group had trouble staying on task and getting steps done, we ended up having lots of work to do right before the due date. This caused the project to be more stressful and rushed. One way I could fix this problem is by letting my group members know what we need to accomplish on a certain day and how. By doing this, my group will know that it is necessary to stay on task and help get the job done. One thing I personally need to work on is having more empathy. At times I felt that my responses to people's ideas or questions might have been more rude then I meant it to be. To fix this I should treat my team members nicely and speak to them in the correct tone of voice. Overall my group and I were able to work together and complete our project.