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!

Direction of reaction of a roller

  1. Oct 23, 2015 #1
    1. The problem statement, all variables and given/known data
    for no 4 , why the reaction force also act downwards ? as far as i know roller can only support the surface perpendicular to it upwards .... but not downwards...
    for no 5 , why the recation force acts upward only ? why not also downards?


    2. Relevant equations


    3. The attempt at a solution
     

    Attached Files:

    • 223.png
      223.png
      File size:
      213.9 KB
      Views:
      59
  2. jcsd
  3. Oct 23, 2015 #2
    From what I read it looks like figure 4 is describing a roller or a pin. The pin would be the one with the downward force. The figure isn't that clear but I think that's what it's showing.
     
  4. Oct 23, 2015 #3
    why The pin would be the one with the downward force?? i thought the support is 'stucked' betwwen 2 surfaces so , depending on the situations , there will be times that the force act downwards , and also there will be time that the forces act upwards
     
  5. Oct 23, 2015 #4
    Your right I wasn't looking at the figure properly. It's a pin and roller between two surfaces so yes depending on the situation the reaction force could be either.
     
  6. Oct 23, 2015 #5

    haruspex

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

    You seem to have answered your own original question here. Do you still have a question regarding no. 4?
    I'm not at all sure what mechanism is depicted in no. 5. The image is not very clear.
     
  7. Oct 23, 2015 #6
    The "rocker" can be thought of as a section of a roller pinned to the end of the rod, so same result as no 3.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Direction of reaction of a roller
  1. Direction of reactions (Replies: 1)

Loading...