Finding Mu Without Friction Data

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The discussion focuses on finding the coefficient of friction (mu) without having direct friction data from a lab experiment. Participants suggest using the mass of the ball, initial velocity, and other known variables to derive mu through calculations involving momentum and forces. One proposed method involves using a cardboard piece on a similar surface to measure friction by applying known weights and using a force scale or elastic band to gauge the necessary force. The conversation emphasizes the importance of experimental setup and creative problem-solving when direct measurements are unavailable. Ultimately, finding mu can be achieved through indirect methods if necessary data is missing.
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Homework Statement


We are doing a lab nearly verbatim to the one at this link, http://dev.physicslab.org/Document.aspx?doctype=2&filename=Momentum_InelasticCollisionsSoftball.xml" However, under #6 in data and procedure I had forgotten to measure frictional force. Is there anyway to find mu or force of friction using the mass of the ball, initial velocity, time in air, distance thrown form box, mass of box and packaging, Fn, and box displacement?


Homework Equations


Inelastic collision formula
momentum formulas

The Attempt at a Solution


N/A stumped without formula to find mu or Ff, data not collected so I don't know how to work the real problem which I can do otherwise. Vf could also help me find Mu by using (0.259kg(vf-0m/s/0.63s))/2.54N = mu
 
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You can find mu if you can take a bit of cardboard to a floor surface similar to the one you used in the experiment. Put any known mass on the cardboard and pull it along the floor with a force scale. If you can't get your hands on a scale, use an elastic band, measure its stretch, then find some way to achieve that same stretch with known forces. Likely you can look up the mass of coins and calculate their mg if no easier method comes to mind!
 
Thanks
 
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