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Contact Forces of 3 blocks

  1. Oct 21, 2009 #1
    blocks A and B have weights of 45 N and 25 N, respectively.

    block A is sitting on a table and block B is attached to block A by a peice of string on a frictionless pulley and block B is hanging off the table. also block C is on top of block A

    Figure 6-48
    (a) Determine the minimum weight of block C to keep A from sliding if µstat between A and the table is 0.20.

    (b) Block C suddenly is lifted off A. What is the acceleration of block A if µkin between A and the table is 0.15?
    2 m/s2

    block a = 45n
    block b = 25n
    block c = 45 -25
    block C = 20N i dont think this is right

    B) cant solve without part A
  2. jcsd
  3. Oct 21, 2009 #2


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    Homework Helper

    Find out the forces acting on A and C. Similarly find out the force acting on B. Find the acceleration of the system. Find the condition for the equilibrium.
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