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Re: Is This Correct?

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On 08/25/2015 12:48 PM, hdblenner@gmail.com wrote:
> 
> "Again, I don't want to try to snow the panel with a lot of equations. I think it is important here to point out that there is a significant difference between kinetic energy and momentum. As you see on top of this exhibit F-303, the energy, one-half mass times the velocity squared, is an expression of what shall we say, the destructive capability of the projectile, and as we all know from our familiarity with Einstein, that energy is conserved. Also momentum is conserved. But in this case, the conservation of momentum is slightly different from the conservation of energy. "
> "Conservation of momentum is a vector quantity, that is, it has direction. If a projectile were moving along and then struck another object, then both of those objects would move off with exactly the same momentum that the first object had coming in. In other words, the linear momentum, the product of the mass and velocity, is conserved and the direction is conserved.
> Let's apply both of these to a hypothetical bullet that is striking a head and losing some velocity."
> "Now, the next line labeled momentum lost, all I have done is taken the product of the mass-this is 162 grains divided by 7,000 - which gives us the mass of the bullet in pounds. Multiply that mass of bullet in pounds times 800 - feet per second, the velocity lost, and we have a quantity, an unusual quantity, 18.4 pound feet per second of momentum which has been deposited by the bullet."
> 
> I find multiple errors. 
> 
why not use few formulas, instead of msny words, and SI units, that I
hoped are used in imperial regions at least withing scientific community ?

(162/7000 ) pounds  * 800 feet/s = linear momentum cca 18.5 pound x feet/s

Where did you find multiple errors ?
If the bullet is trapped by e.g. a block
used to determine the bullet speed,
the block gains initial momentum
18.5 pound x feet/s

-- 
Poutnik ( the Czech word for a wanderer )

Knowledge makes a great man humble, but a small man arrogant.

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Is This Correct? hdblenner@gmail.com - 2015-08-25 03:48 -0700
  Re: Is This Correct? Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-25 13:52 +0200
    Re: Is This Correct? hdblenner@gmail.com - 2015-08-26 07:59 -0700
      Re: Is This Correct? Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-26 17:23 +0200
        Re: Is This Correct? R Kym Horsell <kym@kymhorsell.com> - 2015-08-26 15:45 +0000
          Re: Is This Correct? Sam Wormley <swormley1@gmail.com> - 2015-08-26 11:23 -0500
      Re: Is This Correct? Odd Bodkin <bodkinodd@gmail.com> - 2015-08-26 11:28 -0500
        Re: Is This Correct? Poutnik <poutnik4nntp@gmail.com> - 2015-08-26 20:27 +0200
      Re: Is This Correct? "nuny@bid.nes" <Alien8752@gmail.com> - 2015-08-26 10:20 -0700

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