1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Torque problem involving rolling disk stopped by a force

  1. Nov 9, 2008 #1
    A potter has a stone disk of radius 0.483 m and mass 101 kg rotating at 71.9 rev/min. The potter stops the wheel in 6.54 seconds by applying a wet towel against the rim with a radially inward force of 103 N. Find the effective coefficient of kinetic friction between the whell and the wet towel.
    my work
    angular velocity= 71.9 x 2 x pi /60seconds=7.53
    alpha =7.53 / 6.54=1.15
    Torque=alpha x I = 1.15 x (101) x (.483^2) =27.13 N-M
    27.13 = torque = F r sin 90
    F =27.13/ (0.483)
    F =56.17 Newtons = Frictional force
    56.2 = u Fn
    u=56.2 / (103) ----> 103 is given as the radially inward force, Fn
    u=.545

    why is this wrong? does anyone know why? thanks
     
  2. jcsd
  3. Nov 10, 2008 #2

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Torque problem involving rolling disk stopped by a force
Loading...