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Homework Help: Work Through a Displacement At An Angle

  1. Dec 3, 2007 #1
    1. The problem statement, all variables and given/known data

    Find the work done when a force of 65 N acting at an angle of 170° from the x-axis is applied to an object that moves through a displacement of 2.2 m at an angle of 30°.

    2. Relevant equations

    W = Fcos[tex]\Theta[/tex]d

    where d is the distance moved in the direction of the force.

    3. The attempt at a solution

    I know I am slipping on my distance. The distance the object is traveling in the direction of the force is 2.2 m multiplied by the difference in the angles
    W = ( 65 N ) * cos( 170° ) * ( 2.2 m ) * cos( 150° )

    Obviously this is wrong, I don't understand how to find the distance part of the equation.
  2. jcsd
  3. Dec 3, 2007 #2
    Nevermind, I completely forgot that work is a scalar quantity and that obviously means it results from a dot product. I solved it...

    I just found the vectors of the force and direction, and found their dot product.
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