1. Re: bullet code (was ICONS - dead horse)
Kat wrote:
>----- Original Message -----
>From: Everett Williams <rett at GVTC.COM>
>To: <EUPHORIA at LISTSERV.MUOHIO.EDU>
>Sent: Monday, February 07, 2000 8:15 PM
>Subject: Re: bullet code (was ICONS - dead horse)
>
>
>> On Mon, 7 Feb 2000 20:27:45 -0500, David Roach <roachd_76 at YAHOO.COM>
>wrote:
>>
>> >I gues I did George but do you agree with me that an object can not
>> >fall 999.5 feet/s.
>
>Actually, if you launch it up at 1000fps, and neglecting air resistance, it
>will be falling at 1000fps when it lands at your feet. I doubt a bullet will
>do this, but a depleted uranium arrow with a plain nose and minimal
>fletching prolly will return energy upon landing pretty equal to the launch
>energy. Doing this experiment on the moon or Mars should return the launch
>energy on impact. I'm not guessing where you have set your shoot-`em-up
>game.
Actually, most bullets exit the barrel at speeds well in excess of 1000 fps...
some as high as 5000 fps. No matter how dense the object, or how good the
streamlining, the energy required to break through the various mach numbers
will definitely slow the object hugely. I doubt that more than a 90% of
velocity would be returned at this kind of speed, even though it is just
sub-sonic. As we all know, gravity doesn't care whether it is a feather or a
bowling ball...both receive the same acceleration. The amount of deceleration
supplied by air resistance is the only variable here.
>> >http://www.glenbrook.k12.il.us/gbssci/phys/Class/vectors/u3l2e.html
>> >Here is where I have found all of my info. If I am missing something.
>> >Please tell me. My program is dependant of these equations. Thank you.
>> >
>> >roachd_76
>>
>> Get a CRC handbook. These questions have been settled at this level for
>> several hundred years. The equations that you are using do not correct
>> for atmospheric friction. Atmospheric friction is not relevant to slow
>moving
>> objects,
>
>Actually, it is, under a certain threshold or weight/size, stationary wings
>are very inefficent and flapping wings become the best way to get around.
>And under yet another threshold, the wings needn't be streamlined or
>"airfoil-shaped" to be the best way to get around, the air is like viscus
>pudding. DARPA is still funding this sort of research.
We're talking about ballistic objects here rather than lift-generating, powered
and/or steered objects. Those lead to an almost infinite set of variations.
DARPA's follies led to the medium in/on which we are conversing at
various percentages of the speed of light in a vacuum...at least from your
vacuum to mine
>> but is highly relevant to objects in this speed range...approximately
>> 681 miles per hour...close to the speed of sound at sea level...above it
>> at higher altitudes. Without atmosphere considerations, 999.5 fps is not
>an
>> excessive speed.
>
>Even with atmosphere, most rifles have exit muzzle velocities in excess of
>1000fps.
See notes above. Long before the speed of sound was understood, the effects
of speeds greater than the speed of sound were known and accounted for in
ballistic tables.
>Kat,
>been reading again lately.
Everett L.(Rett) Williams
rett at gvtc.com
