13 October 2014: Air track with magnetic potential energy

Purpose: To verify that conservation of energy applies to this system.

This is the glider on top of the air track system. As possible to see, we have some books ready to place under the track to find angles and distances of equilibrium.

Explanation: First, we set the system where a glider is able to move on an air track, and when its turned on, the surface becomes "frictionless." The glider has a magnet on top of it, and on the end of one side of the air track, there is another magnet, so when they get closer, the glider rebounds. We used a motion sensor on top of the magnet in one of the sides to calculate our values when performing the experiment. To start, we measured the distance which the glider stays in equilibrium away from the magnet. By measuring the distance from the magnet on top of the glider away from the motion sensor, and subtracting by the distance that the glider is away, we got our true distance. After that, we placed books under the air track, creating an angle which we measured with our phones, and we measured the equilibrium distance again. We repeated this eight times, with eight different angles. With the angle and distance, we were able to do a graph of Magnetic force vs. distance and by measuring the slope, we found the force equation. We integrated the area of the graph to get a value for F. From that, we are able to do a graph containing the energies of the system, where KE, PE and total energy were shown.

 This data table shows the angles and forces obtained in our eight different trials.

 This is the graph that we plotted with the values of the Force vs. distance of the system.

This is the integration of the area of the graph Force vs. distance.

 This is the data table including the Energies in the system such as Kinetic Energy(KE), Potential Energy(PE), and Total Energy(T).

This is the graph of the three Energies, where KE(purple), PE(green), and Total(orange).

These are the values that we got for each trial with a different angle. The picture also shows the equation that we used to calculate the force at equilibrium point. The actual numbers were found by plugging the angles in the computer to generate a table.

Summary: After we did all the trials, and got our values, we were able to create graphs, and generate numbers to the Energies and specific times. From those numbers, a graph containing the three energies was able to be created. By looking at it, it is possible to see that the Total Energy is not exactly a straight line, but it does not have extreme oscillations, and most of the time it is close to a straight line of top of the other two energies. This shows that our experiment and values were accurate, because energy is supposed to be conserved. I believe that the oscillations in the graph are due to the fact that the air track surface is not completely frictionless, so friction does affect on the total energy, and also because the table in which the experiment was done was not fully straight, also contributing to a margin of error.