Not logged in. Click HERE to login.

In this lab, you will measure the coefficient of kinetic friction \( \mu_k \) by following a simple procedure using only a weight and a force meter. You will measure \( \mu_k \) by replicating the same procedure used in a typical problem about friction

  1. Get some weight that is between 250 grams and 2000 grams (0.25 kg and 2 kg). Get several force meters capable of of measuring several different forces.
  2. Draw a qualitative free-body diagram of a weight that is being dragged horizontally along a flat surface. There are four forces acting on the weight.
  3. Using a force-meter, find the force of gravity pulling down on the weight. Remember that when using a force-meter, you want to select the meter that is the most sensitive that is not maxed out, as outlined in a previous lab.
  4. Using a force-meter, find the applied force on the weight necessary to pull it at a constant velocity on the flat surface. Make sure you are pulling the weight horizontally and using the best force-meter for the task.
  5. By using the two forces that you measured and by using the concepts outlined in the unit on dynamics, complete a quantitative free-body diagram of your weight while it is being dragged horizontally at a constant velocity on a flat surface.
  6. Find the coefficient of kinetic friction \( \mu_k \) using the formula \( F_{frk} = \mu_k F_N \).
  7. Write a brief paragraph that briefly summarizes the process used to find \( \mu_k \). Make sure that you refer to the formulas and principles of physics you used in your analysis.