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Homework Help: Find the angle to the horizonal using the given information.

  1. Dec 3, 2008 #1
    1. The problem statement, all variables and given/known data
    A man pulls a wooden crate across a floor by a rope.
    Mass of the crate = 15Kg
    Force the man pulls with = 65N
    Acceleration of the box = 20 M/s²

    What is the angle to the horizontal at which the man pulls the rope.


    2. Relevant equations

    W = Fa Δd cosΘ
    W = ½mv²
    (think)


    3. The attempt at a solution

    I clearly don't understand this, but at first I figured I would use W = Fa Δd cosΘ and just rearrange the equation, then I realized, I don't have Work, figured I would find that using
    W = ½mv². Then I realized I don't have Velocity, I can't find velocity without distance and I can't find distance without time.
    I'm lost.
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Dec 3, 2008 #2

    Dick

    User Avatar
    Science Advisor
    Homework Helper

    Don't use work, and don't use velocity. Use mass and acceleration. Use F=ma. Split F into horizontal and vertical components.
     
  4. Dec 3, 2008 #3
    Bah! I feel so silly, this whole unit is on energy and work I became a little closed minded and forgot there were other formulas I could use.
    Thank you !
    =)
     
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