Thomas Harrison

Matt Banks

Scott Teeters

Eric …

EF 151 Final project

Overview

Our project uses the effects of the transference from gravitational potential energy, to kinetic energy. By starting various objects at the top of inclines, gravity causes them to accelerate down the incline thus creating the kinetic energy we need. Then we change that kinetic energy through other parts of our contraption through conservation of momentum. Finally, as the task of the device, we create an amusing chemical reaction.

Construction and Applications

During the design process we had to put our heads together and think of three parts of our project: The initial step that creates the energy that will be transferred through the machine, amusing examples of conservation of the energy we created, and finally a task that our machine will accomplish. To start, we all went home and created rough blue prints of projects. We brought all of them together and sorted through the ideas that we had. Everyone had the same idea for creating our energy; using an incline and gravitational potential energy. We took many of the ideas from our sketches but some we had to take out. We had a practical and effective demonstration of conservation of energy. We wanted a loop in our car track but we could not create enough energy in our machine to produce this effect. Other ideas we threw out were blocks with a domino effect (not enough energy at the end of the effect), and a ball launching and making contact with other parts of the machine (to unstable and inaccurate). After sifting through the many potential ideas we developed our final blueprints, and began construction.

In order to have a stable plane for all of the operations to be held up, we relied on a four and a half foot plank. By using 1x4 inch planks, we built the supports to suspend the balloon pulley, “horizontal domino” effect, and incline track for the marble. An approximate twenty one feet and eight inches of 1x4 planks were used with an additional ten feet of 1x1 pulley support planks. After attaching all of these supports on the base plank, we drilled holes on the side supports to create a place for the axes of domino rotation. At the end of the domino rotation, we built a release for the pendulum out of one 10X2 pillar, a rubber band, a popsicle stick, and a cut out of poster board. The pendulum supports were created with 4 eighteen inch circular dowels and a nine inch crossbar. The actual pendulum uses 9.5 inches of fishing line and a 1.3 oz fishing weight. Car release part of our project has two 10X2 inch pillars where the pendulum hits the car onto the track. Finally the end piece has two eight inch supports suspending another “swing” which releases the dip stick, which creates the chemical effect.

Our project starts with a marble rolling downtwo inclines, converting its gravitational potential energy into kinetic energy. The marbles energy is then transferred into a needle which pops a balloon. This balloon is stuck in a piece of paper and tied to a string, though a pulley, and then to a weight. Once the balloon is popped, there is nothing holding the string in place, therefore causing the weight to be pulled down. The weight falls gaining energy until it hits a system of gears cleverly disguised as ken-ex. There is a series of four “horizontal dominoes”. The weight strikes the first gear causing it to spin and then hit the next gear and transferring its energy. The final spinning gear strikes a lever balancing a weight on it. This weight is tied to a string, thus when it is struck by the gear it falls and then moves in a circular path becoming a pendulum. The pendulum swings hitting another lever with a hot wheels car carefully balanced on it. The force that the weight and the lever apply is just enough to start the car down the track. At the bottom of the track, the car runs into a final lever that pulls a popsicle stick out of a water bottle. The water bottle is filled with vinegar. Resting on top of the popsicle stick is a bottle cap filled with baking soda. When the lever pulls the popsicle stick out of the water bottle, it knocks the bottle cap of baking soda into the vinegar causing a chemical reaction for show and thus completing the task the machine was designed for.

Almost all of the materials we used we had in one of our homes, so we actually bought very little. For the general construction and framework of the device we used a various assortment of 2x4 boards. We then used tape and rigid paper to create the track for the marble and the block for the balloon. We used ordinary string and fishing weights for the pendulums. The balloons were the only thing we actually went out and bought ($1.00from Dollar Tree). The gears are from out first engineering sets; Ken-ex.We found an old hot wheels race track and cars to use in the final part. Last we picked a water bottle and popsicle stick out of the trash (hey we are in college we work with what we got).

Our project did exactly what we wanted it to do, unfortunately it creates a mess. It was hard to get the pendulums to line up perfectly but we learned that gravitational energy can create a lot of energy very easily. If we went back and did it again we would make it so there are less projectile flying every where but other than that we wouldn’t change a thing. We would like to thank you biggest sources of inspiration; the board game Mouse Trap, and the Home Alone movies.

Costs

(The majority of our project we already owned.)

Wood: Preowned. We made approximately 46 cuts. At 20 cents per cut == $9.20
Track: Preowned ======$0.00
Pulley: Bought ======$3.50
Poster board: Bought======$.75
Fishing weights: Preowned======$0.00
Kinects: Preowned======$0.00
Balloons: Bought======$3.00
Dowels: Bought======$3.00
Baking Soda/Vinegar: Preowned======$0.00

Total: $19.45