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Homework Help: Find all three components of vector W

  1. Oct 17, 2012 #1
    1. The problem statement, all variables and given/known data

    W is 8 units in the y-z plane in a direction defined by theta = 120 degrees with respect to the y axis and have a positive z component.

    2. Relevant equations

    3. The attempt at a solution
    Wy=8sin(120) =6.9


    Rz=4.04 units. is this par right? I am not sure how to approach this one. I only how how to deal with x and y axis but not z. Can sombody point me in the right direction? thanks!
    Last edited: Oct 17, 2012
  2. jcsd
  3. Oct 18, 2012 #2
    x, y and z are just labels. What is important is that you have two axes and a vector in their plane, at an angle with respect to one axis.
  4. Oct 18, 2012 #3
    Would I use y or z with the cosin(theta)? How do I know to what goes with sin and cosin?
  5. Oct 18, 2012 #4
    What is the angle with respect to? What do cosine and sine mean? Draw a unit circle, and label the axes with y and z so that things make sense.
  6. Oct 18, 2012 #5
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