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Re: MythBusters: Bringing on the physics bullet drop

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R Kym Horsell <kym@kymhorsell.com> wrote:
> Double-A <double-a3@hush.com> wrote:
>> On Saturday, January 9, 2016 at 6:54:27 PM UTC-8, Sam Wormley wrote:
>>> MythBusters: Bringing on the physics bullet drop
>>> > http://www.wired.com/2009/10/mythbusters-bringing-on-the-physics-bullet-drop/
>>> > If you didn't catch the latest MythBusters (yeah! new episodes), they
>>> > did something straight from the physics textbooks. Just about every
>>> > text has this example of shooting a bullet horizontally and dropping
>>> > a bullet from the same height. The idea is that they should hit the
>>> > ground at the same time. No one but the MythBusters could actually
>>> > show this demo with a real gun.
>>> > The Physics
>>> > I am going to do some calculations, but I want to first write about
>>> > the physics that accompanies this idea (and you can actually do it
>>> > your self without the gun). What physics principle does this demo
>>> > show? Well, it shows two things. First, it shows that the horizontal
>>> > and vertical motion in projectile motion are independent. That is,
>>> > what happens in the y-direction, stays in the y-direction. Really,
>>> > you can treat projectile motion as two separate problems that just
>>> > happen to take the same amount of time. The second thing it shows is
>>> > that the velocity in one direction does not effect the velocity in
>>> > the other direction (which really is the same as the first thing).
>>> > Let me draw two diagrams, one for a dropped ball and one for ball
>>> > shot horizontally.
>> Perhaps if the bullet were fired in a vacuum.
>> Double-A
> 
> 
> Let's look at the artillery tables I posted a ref to earlier.
> It's been hours and I don't think gimp can back up his claims.
> So let's check the opposite.
> 
> The tables include a lot of redundant data so there is good scope
> for developing models and accurately determining whether or not
> the "hang time" of a shell is any different from what you'd expect
> if you just dropped the thing dead from a given height.
> 
> The tables given the flight time and the max height of the shell.
> So we use K12 physics, assume the max height occurs somewhere in the middle 
> of the flight, and just check if the time to drop a dead shell from
> that height is in any way different from the total flight time.
> If not, very prima facie evidence there is no lift.

A glider in equilibrium has a given range for a given initial condition and
a glider certainly has lift.

Ballistic tables just give a range for an initial condition and say
nothing about the how or why the results happen.

Also you continue to ignore the fact that the verticle drag of a dropped
projectile is in general different then that of a fired projectile and
that fact is blazingly obvious.


-- 
Jim Pennino

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MythBusters: Bringing on the physics bullet drop Sam Wormley <swormley1@gmail.com> - 2016-01-09 20:54 -0600
  Re: MythBusters: Bringing on the physics bullet drop jimp@specsol.spam.sux.com - 2016-01-10 03:09 +0000
    Re: MythBusters: Bringing on the physics bullet drop pnalsing@gmail.com - 2016-01-09 21:25 -0800
      Re: MythBusters: Bringing on the physics bullet drop jimp@specsol.spam.sux.com - 2016-01-10 06:27 +0000
        Re: MythBusters: Bringing on the physics bullet drop pnalsing@gmail.com - 2016-01-10 10:00 -0800
          Re: MythBusters: Bringing on the physics bullet drop jimp@specsol.spam.sux.com - 2016-01-10 20:55 +0000
            Re: MythBusters: Bringing on the physics bullet drop pnalsing@gmail.com - 2016-01-10 13:40 -0800
              Re: MythBusters: Bringing on the physics bullet drop jimp@specsol.spam.sux.com - 2016-01-10 22:21 +0000
                Re: MythBusters: Bringing on the physics bullet drop pnalsing@gmail.com - 2016-01-10 15:56 -0800
                Re: MythBusters: Bringing on the physics bullet drop jimp@specsol.spam.sux.com - 2016-01-11 00:20 +0000
                Re: MythBusters: Bringing on the physics bullet drop pnalsing@gmail.com - 2016-01-10 16:58 -0800
                Re: MythBusters: Bringing on the physics bullet drop jimp@specsol.spam.sux.com - 2016-01-11 01:16 +0000
      Re: MythBusters: Bringing on the physics bullet drop Poutnik <poutnik4nntp@gmail.com> - 2016-01-10 10:12 +0100
        Re: MythBusters: Bringing on the physics bullet drop john <johnsefton288@gmail.com> - 2016-01-10 04:38 -0800
    Re: MythBusters: Bringing on the physics bullet drop R Kym Horsell <kym@kymhorsell.com> - 2016-01-10 22:29 +0000
      Re: MythBusters: Bringing on the physics bullet drop jimp@specsol.spam.sux.com - 2016-01-10 23:13 +0000
  Re: MythBusters: Bringing on the physics bullet drop Double-A <double-a3@hush.com> - 2016-01-10 10:27 -0800
    Re: MythBusters: Bringing on the physics bullet drop R Kym Horsell <kym@kymhorsell.com> - 2016-01-11 01:23 +0000
      Re: MythBusters: Bringing on the physics bullet drop jimp@specsol.spam.sux.com - 2016-01-11 03:16 +0000
        Re: MythBusters: Bringing on the physics bullet drop john <johnsefton288@gmail.com> - 2016-01-10 20:08 -0800

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