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Homework Help: I feel dumb asking this one

  1. Sep 14, 2010 #1
    1. The problem statement, all variables and given/known data
    Suppose someone walks 50 meters Northeast, then turns West and walks for 70 meters, and finally turns South and walks 20 meters. What is their East and North components of the net displacement.

    2. Relevant equations

    If I knew one, I could probably figure this one out.

    3. The attempt at a solution

    Tried using /A/= 50cos(x) for East component and /A/= 50 sin(x) and also plugged in the estimated angle for x as well. I don't know if I'm just overlooking something or just not understanding the question or even if I know what I'm doing.

    Any help will be much appreciated.
  2. jcsd
  3. Sep 14, 2010 #2


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    Why do you say x is an estimated angle. If someone is walking Northeast, the angle with the horizontal is exactly 45 degrees. Try drawing a sketch to scale , placing the tail of the 2nd vector on the arrow of the first vector, then the tail of the third vector on the arrow of the 2nd vector. The net displacemnt is the vetor pointing from the origin to the arrow of the third vector. That will give you a rough idea of the net displacemnt vector. Analytically, sum all x components to get the x component of the net vector, and sum y components to get the y component of the net vector. But i don't get an east and north component of the net displacemnt, i get a west and north component.
  4. Sep 14, 2010 #3
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