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Basic lineal motion formulas

  1. Sep 17, 2012 #1
    One thing I enjoy as a new physics student is using formulas. I have been playing with the fundamental formulas in terms of units rather than their names.

    That is instead of a=v/t
    m/s/s=(m/s)/s

    or v=at
    m/s=(m/s/s) x s
    m/s=m/s

    Simple maths yea, but when im getting to the bigger formulas im having trouble, perhaps they just dont work the way i am thinking but if someone could enlighten me that would be great..

    S=(1/2)at^2
    m=(1/2)x(m/s^2)x(s^2)
    m=(1/2)x(m)

    why do i get m = half m?

    v^2 = 2as
    m^2/s^2 = 2(m/s/s) x m
    m^2/s^2 = 2 x m^2/s^2
    m/s = 2 x m/s

    again, there is a x2 factor there.

    am i just thinking about this too much?
     
  2. jcsd
  3. Sep 17, 2012 #2

    HallsofIvy

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    Staff Emeritus
    Science Advisor

    If you are only looking at the units you are throwing away any "dimensionless" constants in the formulas. From that point of view, there is not difference between "m" and "m/2"- both have dimensions of "meters" which is all you are looking at.
     
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