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Homework Help: Newtons 2nd law

  1. Jan 15, 2008 #1
    A 29.8kg crate is at rest on a level floor, and the coefficient of kinetic friction is 0.338. The acceleration of gravity is 9.8 m/s. if the crate is pushed horizontally with a force of 188.535 N, how far does it move in 5.88 seconds?

    i really need help with this...thanks!
     
  2. jcsd
  3. Jan 15, 2008 #2
    So use Newton2 law's formulae: F=ma; s=(at^2)/2
     
  4. Jan 15, 2008 #3
    so i did 188.535= (29.8) (A)
    A= 6.33

    D=(6.33)(5.88)^2 /2
    =109.43

    but thats not the right answer i dont know what im doing wrong
     
  5. Jan 15, 2008 #4

    rock.freak667

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    Homework Helper

    The weight of the box is 29.8*9.81= (*)N
    therefore the normal reaction,R= (*) N

    the frictional force=uR where u=coefficient of friction.

    find the resultant force and then equate that to ma
     
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