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I Why do we need projection of vectors

  1. Jul 26, 2016 #1
    I know that projection of vector B on A is ||B||cos(theta) where theta is the angle between vector A and B . But why do we find it . Is there any application for this
  2. jcsd
  3. Jul 26, 2016 #2
    it is useful in many applications when you want to know the parallel contribution of B to the total, eg in resolving a force or calculating work ie;

    work = Force X distance in direction of motion
  4. Jul 26, 2016 #3
    Ohkkk , thanks
  5. Jul 26, 2016 #4
    read here from

    https://en.wikipedia.org/wiki/Work_(physics); [Broken]

    "This calculation can be generalized for a constant force that is not directed along the line, followed by the particle. In this case the dot product Fds = F cos θ ds, where θ is the angle between the force vector and the direction of movement.
    Last edited by a moderator: May 8, 2017
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