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Homework Help: Total work of two blocks

  1. Feb 13, 2009 #1
    1. The problem statement, all variables and given/known data

    Two blocks are connected by a very light string passing over a massless and frictionless pulley . The 20.0 N block moves 75.0 cm to the right and the 12.0 N block moves 75.0 cm downward.

    Find the total work done on the 20 N block if [tex]\mu _s\;[/tex]=(coeff. of static friction)=0.500 and [tex]\mu _k \;\;\;\; [/tex]=(coeff. of kinetic friction)=0.325 between the table and the 20 N block.

    2. Relevant equations
    [tex]w=f\cdot d[/tex]
    [tex] f_k=\mu_k\cdot n[/tex]
    [tex] f_s\leq\mu_s\cdot n[/tex]

    3. The attempt at a solution
    w=[7.5N-(.325)(20N)](.75m)=.75J--wrong.
     
  2. jcsd
  3. Feb 13, 2009 #2
    Never mind. I've solved it myself through some careful research and considerable effort. It is unfortunate that no one was able to answer this in time. Perhaps you people want some monetary compensation? Or maybe no one liked my problem. Not particularly hard, is it?
     
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