Rube Goldberg was a cartoonist in New York city who made several comics about overly complicated machine that completed simple tasks.
Project Goal: To learn about simple machines and energy transfers.
Requirements: Project must contain at least five simple machines. (lever, pulley, wedge, screw, wheel and axle, inclined plane)
Project must contain at least four energy transfers.
Project must have at least ten discreet steps.
The project must be presentable at he Rube Goldberg presentation.
Project History: Before we had started building our project, our group sat down and made a two-dimensional diagram detailing what our project was going to look like. The next day, we got our sixteen square foot board and began construction. Originally we planned to stand the board up and make our project two-dimensionally, but we realized that it would be stronger and more interesting if we cut the board in half and made it more three-dimensional. Over the next few days, we modified our original design to be more realistic and reliable. We finished building the project after eight days, then spent the next day painting our project a patriotic red, white, and blue. For the last 2-3 days, we calculated force, velocity, energy, and impulse, made our presentation, and made some final touches. We faced many challenges and made many changes during our project. One noteworthy change was the decision to use a 200 gram weight to start our project. We realized it was more accurate and reliable than the silver ball we had been using. It was also a more interesting start. Another change we made was the decision to use a wheel and axel in the beginning of our project, as opposed to a screw. The wheel and axel approach was much easier to do than the screw; it was also more reliable.
Steps in our Project: In our first step, the 200g cylindrical mass is rested on an inclined plane and held in place by the operator, using the wheel and axel. In step two the cylinder is released and rolls across a flat plane and falls into a hole. In step three, the cylinder strikes a silver ball with 8.2N, setting it into motion down some steps. In step four the ball rolls down two switchbacks. In step 5 the ball hits a first-class lever raising the opposite side. In step 6 an orange ball rolls down and pulls on a string. The string goes around a pulley to turn the lateral force into a vertical force, so that in step seven the lever can be raised up, which allows the other lever in step nine to swing down and hit a golf ball. In the final step , the golf ball hits a cup, spilling water onto a LEGO TM guy. Here is a video of our project working. (Before it was painted)
Concepts:
We used many concepts while constructing our machines. Here are a few noteworthy ones.
Force: Force can be described as a push or pull. It is calculated with the formula F =ma.
Acceleration: Acceleration is the rate of change in an object's motion. It is calculated with the formula ΔV/ΔT.
Speed/Velocity: Speed is the amount of distance an object covers in a given amount of time, and velocity is speed with a direction. It is calculated with the formula Distance/Time
Mechanical Advantage: Mechanical advantage is how much easier the machine makes work. This is calculated by dividing the input distance by the output distance.
Kinetic Energy: Kinetic energy is how much energy an object has due to motion. It is calculated by multiplying 1/2 mass and velocity squared. Kinetic energy changes to potential energy as something falls.
Impulse: Impulse is the amount of force applied for a given amount of time. It is calculated by multiplying force and time. When an object hits another object there is an impulse.
Momentum: Momentum is how much energy a moving object carries with it. It is calculated by multiplying mass and velocity. When the golf ball rolls down the inclined plane it has momentum.
Work: Work is the amount of force applied to move an object a certain distance. It is calculated with the formula W = F*D.
We used many concepts while constructing our machines. Here are a few noteworthy ones.
Force: Force can be described as a push or pull. It is calculated with the formula F =ma.
Acceleration: Acceleration is the rate of change in an object's motion. It is calculated with the formula ΔV/ΔT.
Speed/Velocity: Speed is the amount of distance an object covers in a given amount of time, and velocity is speed with a direction. It is calculated with the formula Distance/Time
Mechanical Advantage: Mechanical advantage is how much easier the machine makes work. This is calculated by dividing the input distance by the output distance.
Kinetic Energy: Kinetic energy is how much energy an object has due to motion. It is calculated by multiplying 1/2 mass and velocity squared. Kinetic energy changes to potential energy as something falls.
Impulse: Impulse is the amount of force applied for a given amount of time. It is calculated by multiplying force and time. When an object hits another object there is an impulse.
Momentum: Momentum is how much energy a moving object carries with it. It is calculated by multiplying mass and velocity. When the golf ball rolls down the inclined plane it has momentum.
Work: Work is the amount of force applied to move an object a certain distance. It is calculated with the formula W = F*D.
Reflections: Overall, I'd say our project went great. Our group got along well, and never really needed mediation. At first, we weren't working as quickly or efficiently as we should have been, but each day we improved on that. One of the most important things I have learned is how to work with different types of people. I also learned a lot about construction. Before this project I wasn't very familiar with power tools or construction methods. I could have managed my time better during this project. Our group as a whole spent too much time on small details, and not enough time on the important things. I also could have stepped down more and let other group members have a chance to lead. One of our biggest pits was when we were trying to make the screw for our fifth simple machine, and couldn't do it. We decided to change that out for a wheel and axel to overcome this problem. A peak was when we realized that the cylindrical 200g weight could be used in our first step, and switched out the ball for it. Another peak was when we finished painting our project and it looked super cool. This project was a great learning experience in life skills and scientific content.