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Effects of change of origin

  1. Feb 5, 2013 #1
    In a general situation, how do you change origin (mathematically speaking) in a physical context i.e. with position vectors, constant vectors, unit vectors to certain directions ... ?

    I am a bit confused with the concept.
     
  2. jcsd
  3. Feb 5, 2013 #2
    If You have a Cartesian co-ord system of x, y, z with origin set at 0,0,0 then you need to add or subtract from the x, y, z of the function by the amount you are moving the origin.

    Ie if y=3x at origin x0,y0 then at a new origin x4,y3 the function will be y+3=3x+4 or y=3x+1.
     
  4. Feb 5, 2013 #3
    So if I have an equation x'=(x(cross)n)+a
    where x is the position vector, x' time derivative, n unit constant, a constant, then I get changing by x->x+c:
    (x+c)'=((x+c)(cross)(n+c))+(a+c)
    is this what you meant?
     
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