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Newtons first law: implications on kinetic energy

  1. Nov 22, 2006 #1
    Newton's THIRD law: implications on kinetic energy

    edit: after thinking about it a little more, I realized something. After having landed, my kinetic energy becomes what it began as (practically zero). nvm then.
    Last edited: Nov 23, 2006
  2. jcsd
  3. Nov 23, 2006 #2

    Andrew Mason

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    I lost you when you started talking about pressure*volume. Are you talking about the atmosphere? How does kinetic energy and radiation affect PV?

    Also, are you suggesting that the kinetic energy of the earth is equal to the kinetic energy of the person jumping?

    Last edited: Nov 23, 2006
  4. Nov 23, 2006 #3
    Title is wrong - I should have said Newton's THIRD Law

    No, not the atmosphere.

    Well, these may have common cause. In an engine, when fuel is burned, the molecules of the fuel increase in temperature. This affect the kinetic energy of the particles and also results in radiation. The change in pressure*volume is reflected by this (see P-V diagram).

    Actually, now that I think about it, this isn't correct.

    The forces on both objects may be the same at a given moment in time. But the displacement is different for each object if each object has a different mass. Therefore the change in kinetic energy will be inversely related to the mass of the particle of the two considered. If something weighs 100 more, the change in its kinetic energy over the course of the change forces will be 100 times less (due to having a equal but opposite force on it at all times but over 1% the distance... also: [itex]\Delta x = .5at^2[/itex]).

    Last edited: Nov 23, 2006
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