Friction between rotating objects

  1. In physics, we learned about friction between one object sliding across another, but when we got to torque and angular velocity, etc, there was never any mention of how to calculate friction between 2 objects rotating in place. Say you have a plate on top of a table and it is rotating about the center of the plate. How would you calculate the friction between the plate and the table if the coefficient of friction is known?
  2. jcsd
  3. malawi_glenn

    malawi_glenn 4,725
    Science Advisor
    Homework Helper

    change to spherical coordinates and integrate over the surface.
  4. tiny-tim

    tiny-tim 26,016
    Science Advisor
    Homework Helper

    Yes … specifically, if you divide the plate into concentric ring-shaped bits, each bit of length 2πa will have the same behaviour under friction as a straight rod of the same mass and of length 2πa. :smile:
  5. Thank you guys for your help. Im going to see if I can figure out this problem I was working on now
Know someone interested in this topic? Share this thead via email, Google+, Twitter, or Facebook

Have something to add?