Proficiency 4

1. Scissors cuts a string, attached to a car
2. Car rolls down ramp, hits dominoes
3. Dominoes hit each other, fall in pulley
4. Pully falls and raises on the other side, releases ball
5. Ball rolls down inclined plane, screw, hits dominoes
6. Dominoes hit each other for a long while, hit ball
7. Ball rolls into cup

This is the final Rube Goldberg we did, after about 6 attempts from other ideas. We completed it in a basement instead of the science room as we had planned.

Inclined Plane

An inclined plane is designed to allow you to move from point A to point B in an easier way. For instance, if you are moving and have to carry heavy boxes out to a moving van, you can use a ramp to reduce the mechanical energy you have to use. Because the ramp supports the box underneath, it requires less mechanical energy to move it. The longer and shorter the ramp, the more mechanical advantage, and the less mechanical energy is required to move the box. In converse to that, the steeper and shorter the ramp, the more mechanical energy is required to move it.

In the case of the Rube Goldberg, we had a toy car rolling down an inclined plane. When the car is being held at the top of the ramp, it has potential energy as it is not in motion  but has the potential to be in motion. As it is released, the inclined plane allows the car's potential energy to convert to kinetic energy. Another inclined plane, with an almost non-existent slope allowed the car to decelerate and trasfer its kinetic energy back into potential energy.

Wheel and Axle
The wheel and axle in our Rube Goldberg was part of the toy car. As it was held above the inclined plane thecar had a potential kinetic energy which means that it had a potential of becoming active. When the car was released, the potential energy transfered into kinetic energy, as it became active with its movement. Finally, when the car rolled onto the other inclined plane, its kinetic energy reverted back to potential energy, because of the slope of the plane.

Pulley
A pulley utilizes mechanical advantage to transfer energy in a similair fashion to the other simple machines. Because there is an equal weight on both sides of the pulley stays in rest wherever it is placed, allowing it to build up potential energy in its dormancy. When we rolled the car into it, the pulley's energy was transfered from potential into kinetic as it begins to move. After it gains acceleration and hits the floor, the pulley regained its potential energy.

Lever
When a first class lever is resting on its fulcrum, it has a wealth of potential energy. Then when an unbalanced force acts upon it, in this case the pulley, the lever tilits until it reaches the floor. This motion transfers the stored up potential energy into kinetic energy but when it touches the floor and stops, the energy is converted back into potential.

Screw
Because a screw is am inclined plane wrapped around a cylindar, it transfers energy in much the same way. In our Rube Goldberg, we had a ball get hit by dominoes and roll down a screw. Before it is hit by the dominoes and because of its position partially insied the screw, it has potential energy. When the ball is hit and begins to roll down the screw, the screw transfers the potential energy into mechanical and kinetic energy. Finally, when the ball rolls out of the screw the energy reverts back to potential.
Wedge
For our Rube Goldberg, the wedge that we utilized was a scissors. This is actually a pair of wedges the work together to cut somrthing. The wedges begin in an opened position, where they have potential kinetic energy, the potential to become active. When the scissors is hit by a ball, the weight causes them to become active and close. This is a transfer of energy from potenial kinetic into kinetic. After the scissors close, the revert back to a stage of potential energy.