1. Open the program found here.
   
2. Look at all the different possible surfaces and pick the one that you would like to study.
   
3. Use the up and down arrows to change the mass of the object on the table.  I would like you to do 10 different masses through the course of this experiment.
4. Set up a data table to track the mass of the object on the table, the force normal (equal to gravity), and the force applied (equal to friction).
5. Hit the start button and watch as the person pulling on the box increases the force applied.  At some point the box should start to move across the table at a slow and steady speed.  Write down what seems to be the average force needed to pull the object at a slow and steady speed.
6. Record your estimated force in your data table as your force applied/force friction column.
   
7. Repeat this procedure for 9 other masses.
   
8. Make a graph of force friction vs. force normal. (There’s an example on this page.)
9. Give a sentence of conclusion telling what you learned and sources of error.

 

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