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Consider the momentum as the acceleration energy?

  1. Dec 13, 2009 #1
    yes is from Sweden and my English is not good, but will try to do as best as possible. My question is:
    why can not consider the momentum as the acceleration energy?

    I know that:
    Impulse is change in momentum which is not the same as energy
    Impulse can be expressed either as F * (delta) t or m * (delta) v since it is the same thing. That the expressions are as follows from Newton's 2nd Kraftlag together with the definition of acceleration: (delta) v / (delta) t

    but as we move into the energy we see that energy is defined as:
    W = mv ^ 2 / 2
    but what is the difference between rörelsenergi and momentum:

    I couple of things:
    An important difference is that momentum is always kept in a collision between two or more objects. The kinetic energy conservation is generally not in a collision.
    Another difference between kinetic energy and momentum is that kinetic energy is a scalar (ie, has size but not direction) while the momentum is a vector (ie, both the size and direction)

    but I can not really understand what the difference between momentum and kinetic energy (accelerating energy)
  2. jcsd
  3. Dec 13, 2009 #2
    Re: momentum

    if we compare the energy between, thus förendringen Middle two speeds we get that the change in energy is:
    http://www.pluggakuten.se/wiki/images/8/8f/Untitled11111.jpg [Broken]
    I can not see a big difference between them, the only thing that separates them is that we have abbreviated removed (delta)stretch
    Last edited by a moderator: May 4, 2017
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