Write - Up

The purpose of this project is to demonstrate the fundamentals of a Rube Goldberg machine by blowing out a candle. The mechanics would allow for a certain time allotment of candle light before it would be automatically blown out. This could give you the option of lighting the candle, getting ready for bed, and just as you jump into bed, the light would be snuffed out.

In our devise, we used a chair, a bass pedal, a notebook, a candle, some string, a water bottle, and a weight to hold down the string. To calculate the potential and kinetic energy, we need to find the height of the water bottle from the bass pedal. To find potential energy, we must multiply mass (of the water bottle), times the acceleration of gravity, and the height (the distance between the water bottle and the bass pedal).

The energy transformations take place initially when the thermal energy burns the string. Then, the potential energy of the water bottle is converted into kinetic energy as if falls on the bass petal. The impact of the bass petal is caused by the kinetic energy of the water bottle. That energy is transferred to the notebook, and it falls over, then blowing out the candle with a rush of wind.

Data Tables:

During initial testing –

 Trial 1 Trial 2 Description of candle Large candle, flame somewhat protected Small, exposed flame Successful / unsuccessful? Unsuccessful Successful

During final testing –

 Trial 1 Trial 2 Distance of notebook from candle Too far to blow out candle Close enough to blow out candle Successful / unsuccessful? Successful Successful

The complete, successful version of our model incorporates a smaller, more exposed candle, which is blown out by the notebook’s gust of air. Also, we made sure to put the notebook at a close enough distance to the candle so that it would be successful. All problems and difficulties that this project faced seem to have been dealt with; therefore, it can be trusted to perform successfully when tested. The potential energy loss that the machine may face would be a poor energy transfer between the water bottle and the bass pedal. However, only a small amount of energy is required to move the bass pedal, so it was never a problem.

The main challenges we faced in this project was including all of our planned ideas in the final, built machine. The machine worked as great as we had hoped, and it is very reliable. What I liked about this project was that it all worked according to plans, and we only had to make a few changes in our plans. Some future changes we would recommend would be a more tightly – constructed apparatus, and more specific calibrations. This would ensure a precise experiment every time. In this project, the margin for error was very wide, so it was not necessary to follow a strict set of measurements. This project was also fairly simple, and it took less time than we expected to construct and perform. If we had more time and resources during the planning of the project, we would have added more equipment, and probably used electrical devices. Overall, one thing we learned gained from the project was a further understanding of energy transfer, and we had fun doing it.

Word File:

prewriteuprough.doc