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!

Rolling and translation motion

  1. Mar 10, 2007 #1
    1. The problem statement, all variables and given/known data
    I throw a ball rolling and moving through the a flat surface. I may say that friction is slowing down translation motion, but increasing rotational motion, so when the ball stops moving, why is it not rolling? That's confusing me a bit. What can you say?
     
    Last edited by a moderator: Mar 10, 2007
  2. jcsd
  3. Mar 10, 2007 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Can you rephrase your question. If the ball is at rest (no translational motion or acceleration) how can it be rotating with friction present? (Is that what you mean by rolling?)
     
  4. Mar 10, 2007 #3
    I am sorry, my english did not let express as well as I would like to. The ball initially has rotational and translational motion. :approve:

    Thanks for replying.
     
  5. Mar 10, 2007 #4

    Doc Al

    User Avatar

    Staff: Mentor

    OK. If the ball starts with a motion such that the speed of its bottom surface (with respect to the floor) is anything other than zero, then kinetic friction will be exerted on the ball in a direction that opposes the slipping between the surfaces.

    For example: If the ball starts out in pure translation, then friction will slow the translation and speed up the rotation--up until the point that the ball rolls without slipping.
     
  6. Mar 10, 2007 #5
    And if the ball starts out with pure rotation?

    Thanks again for helping me.
     
  7. Mar 10, 2007 #6

    Doc Al

    User Avatar

    Staff: Mentor

    The direction of rotation will determine which way friction will act and the direction that it will roll. This time kinetic friction will speed up the translation and slow down the rotation until the ball rolls without slipping.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Rolling and translation motion
  1. Rolling Motion (Replies: 2)

  2. Rolling Motion (Replies: 24)

  3. Rolling motion (Replies: 3)

Loading...