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!

1-dimensional non-conservative force that depends on position?

  1. Oct 9, 2012 #1
    1. The problem statement, all variables and given/known data
    Does there exist a 1-dimensional non-conservative force that depends on POSITION (not velocity)?


    2. Relevant equations
    N/A


    3. The attempt at a solution
    I've given this a lot of thought, and I can't come up with anything! Friction doesn't work, etc...

    Any help would be greatly appreciated!! :)
     
  2. jcsd
  3. Oct 9, 2012 #2

    berkeman

    User Avatar

    Staff: Mentor

    Welcome to the PF.

    Why doesn't friction work?
     
  4. Oct 9, 2012 #3

    rcgldr

    User Avatar
    Homework Helper

    Would the hysteresis in a rubber band qualify it as a non-conservative?
     
  5. Oct 9, 2012 #4
    Friction doesn't fit the definition because it is not dependent on position. Hysteresis... not sure. That seems more dependent on tension, but if it can be quantified in terms of position, that might work. What do you think?
     
  6. Oct 9, 2012 #5

    berkeman

    User Avatar

    Staff: Mentor

    I think friction can work if you put one condition on it. Can you think of that condition?
     
  7. Oct 9, 2012 #6
    Are you referring to static vs kinetic? As far as I can tell, friction depends on some velocity being present (kinetic), or not present at all (static). As far as I can imagine, it doesn't depend on position, but I would love to hear which condition you refer to :)
     
  8. Oct 9, 2012 #7

    berkeman

    User Avatar

    Staff: Mentor

    We can't give out answers here at the PF (it's against the rules for schoolwork questions). So you will need to think on it more. I'm referring only to kinetic friction. Think about what you are trying to achieve in this problem, and see if you can think of what to do with friction to accomplish it...
     
  9. Oct 9, 2012 #8
    Ok, so say you have a block sliding along a surface. The only way I can think of making the force of friction dependent on position is if the coefficient of friction changes along the surface. For example, if you have sand paper on the surface with changing grit values from left to right, then yes, the force of friction would absolutely depend on position.

    I'm not sure if that's what my prof is going for, but I'll give it a whirl... I can't think of any others!
     
  10. Oct 9, 2012 #9

    berkeman

    User Avatar

    Staff: Mentor

    That's exactly what I was thinking of -- good for you for coming up with it! I think it satisfies the problem statement... The non-conservative force is position dependent, but not velocity dependent.
     
  11. Oct 9, 2012 #10
    Thanks for your replies :)

    The forum looks great, I don't know why I didn't find this earlier. I still have 1.5 more years of my degree program left, so this forum will undoubtedly be handy!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: 1-dimensional non-conservative force that depends on position?
Loading...