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!

Help finding coefficient of friction

  1. Nov 15, 2006 #1
    Hey, I was wondering if someone could help me with this statics problem.

    The question is: "The 1600kg car is just beginning to negotiate the 16* ramp. If the car has rear-wheel drive, determine the minimum coefficient fo static friction required at B.

    My FBD:
    [​IMG]

    The answer I keep getting is 0.395, but the book says Us = 0.365.

    I'm about to type up my work in a second
     

    Attached Files:

  2. jcsd
  3. Nov 15, 2006 #2
    [tex]\Sigma \vec{F}_{x} = \vec{f}_{B} - \vec{A} sin(16) = 0[/tex]
    [tex] \Sigma \vec{F}_{y} = \vec{B} + \vec{A} cos(16) - G = 0 [/tex]
    [tex] \Sigma \vec{M}_{B} = -1.475*G + 2.545*\vec{A} cos(16)[/tex]

    .....From moment equation, A = 9463N
    ....From Fy equation, B = 6599N
    ....From Fx equation, Fb = 2608N

    Using Fb = u*B, I get u = 0.395, which is not the correct answer. I'm not really sure what I'm doing wrong here.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?