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Homework Help: Block on incline

  1. Oct 28, 2008 #1
    Can someone tell me if I'm doing this problem right?
    1. The problem statement, all variables and given/known data
    Here is the picture of the problem:
    http://i210.photobucket.com/albums/bb23/Kyashii628/block.jpg [Broken]

    In my FBD, I have Fg pointing down, Fgy perpendicular to the incline and pointing down, Fgx parallel to incline pointing down the ramp (to left), kinetic friction pointing up the ramp (to right), and normal force pointing opposite from Fgy.

    2. Relevant equations
    Fnet= -ma
    fk- Fgx= -ma
    u(Fn)= -ma
    u(345.0615986)= 648.9664808 -240
    u= 1.182397583
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Oct 28, 2008 #2


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    Gold Member

    good, but remember in your FBD, that once you resolve Fg into its x and y components, you should 'cross out' the Fg downward force.
    I'm sure you meant u(Fn) = fk
    you have your mg(sin theta)and mg(cos theta) reversed.
    Correct your error and your result should be fine.
    Last edited by a moderator: May 3, 2017
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