Roller+Coaster+Lab+RJD

=Conservation of Energy on a Roller Coaster= Date of Publication (Date of Most Recent Edits)


 * Participants**: Jill, Rachelle, Drew
 * Purpose**: The purpose of this lab is to examine how mechanical energy (kinetic and potential energy) can be changed by outside forces.
 * Lab Documents**: [[file:Roller Coaster.doc]]

First, we recorded the speed of the cart at each of the thirty points, using the Beespi in km/hr. We then measured the height of each of these thirty points, using a meter stick. We then imported the data into LoggerPro, including the length from each point to the next point, the measured heights, and the velocity of the cart. We then converted the km/hr to m/s using a “new calculated column” on LoggerPro. We then calculated the Kinetic Energy, Mechanical Energy, and the Potential Energy. We also calculated the force exerted at each point (friction). For all calculations we used new calculated columns. These calculations were used to figure out the work done by the chain of the roller coaster.
 * Brief Description of Experiment**:

This is the Roller Coaster we used to examine the work done by the chain and how mechanical energy, kinetic energy, and potential energy, can be changed by outside forces. media type="file" key="RollerCoaster Movie Small.wmv" width="300" height="300"
 * Data**:

1.) km/hr - m/s = multiplied km/hr by 1000. Then divide by 3600 seconds. 2.) Kinetic Energy = (.5) * (mass) * (velocity)^2 3.) Potential Energy = (mass)*(gravity or 9.8)*(height in cm) 4.) Mechanical Energy = (Kinetic Energy) + (Potential Energy) 5.) Force Exerted (Friction) = Delta (Mechanical Energy) / Delta (Distance to Point)
 * Sample Calculations:**

From this lab we were able to see that throughout the cycle of the roller coaster, some energy was gained and some energy was lost. If we look at our data we see that the mechanical energy at the beginning of the cycle is numerically very close to the mechanical energy at the end of the cycle (.532 and .522). This would prove that the overall energy was conserved even though at different parts of the cycle some energy was gained and lost, in the end it evened out. This proved the law of conservation of energy correct for a roller coaster.
 * Results**:

**1. What external forces did you identify as removing energy from the roller coaster system? Into what form of energy do you think the mechanical energy was converted via these forces?** The major external force that was removing energy from the roller coaster was gravity, as the cart began to go through the loop gravity overall slowed the cart down. The mechanical energy was being converted into gravitational potential energy. The external force that was adding energy to the system was the ramp (that had a motor) that brought the cart to the top of the roller coaster. The mechanical energy of the cart was being converted to potential energy at this point because as the cart was being brought up the ramp the cart was gaining energy which was then being stored until it went down the ramp again. **4. At what point in the motion of the roller coaster was mechanical energy being dissipated (lost from the system) most quickly with respect to distance traveled? How about with respect to time? With respect to both distance traveled and respect to time, the mechanical energy was lost from the system most quickly right after the big drop off and as the cart was entering the loop. ** (points about 6 through 10).
 * Lab Questions**:
 * 2. What external forces did you identify as adding energy to the roller coaster system? From what form of energy do you think the mechanical energy was converted via these forces?**
 * 3. Break the motion of the coaster into 4 pieces as described below. What fraction of the total mechanical energy from the top of the coaster was lost in:**
 * 1) **The first big drop?** 10% was lost
 * 2) **The entrance to the loop?** 30% was lost
 * 3) **The exit of the loop?** 50% was lost
 * 4) **The back turn?** 60% was lost

In this lab we were supposed to evaluate the law of conservation of energy for a roller coaster. Through the experiment we discovered that this law seemed to be proven true. The total mechanical energy at the beginning of the roller coaster cycle had almost the exact numerical value as it did at the end. This proves the energy was conserved throughout the whole cycle of the roller coaster. We noticed; however, that in many different points throughout the cycle energy had been gain and lost, but overall the gains and losses made up for each other which are why the starting and ending mechanical energy values were practically the same. The major inaccuracies in our data were caused by human error in the sense that our placement of the beespi may not have been as accurate as it could have been. To improve this lab it would have been better to measure the speed using the beespi several times at each point, and then averaged all the speeds together. Unfortunately we didn’t have that kind of time so we just did the best we could.
 * Conclusion**: