Marble and Ramp Data Analysis
- In this lab, the student typically changed the GPE by changing the height of the ramp or marble.
- This changed the distance that the wooden block moved. The block distance is our proxy for KE.
- Each group likely had its own unique setup. We will attempt to normalize the classes' data sets to compare results.
- At times it is difficult to visualize the relationships among numbers if they are in an inconvenient form. The data table on the left contains a list of measurements.
- This raw data can be converted into a form that is easier to understand by dividing all the measurements by the value of the smallest (as shown in the second table on the right).
- This process is called normalizing the data. Now it is easier to see the third measurement is 19 times larger than the first measurement.
Example Table 1 Raw Data (mm) 0.0625 0.125 1.1875 0.875 Example Table 2 Raw Data (mm) divided by = normalized data 0.0625 0.0625 1 0.125 0.0625 2 1.1875 0.0625 19 0.875 0.0625 14
- There are many ways to normalize data. This is just one way.
- Prepare a table of your data.
- Record the height measurements.
- Divide all the height values by the smallest height value. Record the quotient as the normalized height.
- Record the distance the block moved. This is our stand-in for KE (our proxy measurement).
- Divide all the KE proxy values by the smallest KE proxy value. Record the quotient as the normalized KE proxy.
|Height||Normalized Height||KE proxy (distance block moved)||Normalized KE proxy|
- Make a graph of the normalized Height (x-axis) vs. the normalized KE proxy (y-axis).