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dsr View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dsr Quote  Post ReplyReply Direct Link To This Post Posted: February/07/2012 at 18:12
Trigger29,

Your statement is true that the bullet "sees" both components of drag. But for this problem it is proper to ignore the vertical segment of drag. Drag is a function of velocity squared . The vertical velocity is 13.86 ft/s at contact and assuming constant velocity for the horizontal component of 2850 ft/s. The squared velocities are 192 vs 8,122,500 respectively and the ratio is 0.0000236503 so it is safe to ignore the vertical air drag
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Kickboxer Quote  Post ReplyReply Direct Link To This Post Posted: February/08/2012 at 06:13

Proof of -1 * x = -x, using simple math:

 

Math fact:  Any number times zero equals zero.

 

0 * x = 0

Now, zero can be written as (1 + -1) which follows from the definition of -1... -1 is the additive inverse of 1, ie., the number that when added to 1 give the additive identity element, 0.

 

(1 + -1) * x = 0

 

Applying the distributive property:

1*x + -1*x = 0 (simplifying) 1x + -1x = 0, or x + -x = 0 (from the fact that 1 times any number is the same number),

Which leads us to the fact that the number that when added to x gives us zero is -x,

Therefore:

-x = -1*x,

We now use this theorem to prove that -1 * -1 equals 1:

 

-1 * -1 = -(-1)

        = 1

 

This proof involves only simple elements of math, the associative and distributive properties and basic 1st year math facts.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: February/08/2012 at 11:08
you used elements from ring theory in your proof, but didn't show that the basic assumptions were part of a larger group of sets having the same property (or lacking them)
0 * x = 0 is not a math fact -- it only applies to a certain group of rings, homomorism has not been established in your arguement
 
(1+-1)*=0   you use the fundamental property of rings
 
as a side note robertsons reference to topology above and the proof that the coffee cup is a doughnut can use a ring theory proof from cohomology of topological spaces.
 
use of operations are illustrations of the proof , not a proof of it.
 
example
yes, we have no bananas
a=1       b=1
if a and b are 2 positive numbers then -a and -b are negative numbers with product
-a*-b=(-1*a)*(-1*b)=-1(a*b)    a fundamental property of rings    (yours above is the same, only more specic)
minus a means not a   minus minus a means not not a, which means yes a
if you do not like this solution, I guess you think it is correct
-a*-b=-1*a*-1*b=(-1)*(-1)*(a)*(b)=(-1)^2*a*b=1
 
but (-1)^2=-1
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Post Options Post Options   Thanks (0) Thanks(0)   Quote preacherman Quote  Post ReplyReply Direct Link To This Post Posted: February/08/2012 at 13:19
go to hornady.com there  you will find a ballistic calculator. Your BDC and bullet weight as well as humidity will effect the answer. First, is the bullet 30 cal? 338cal? 7mm? anyway you take your rifle standard range do the raw data then find your appropriate MOA in drop to the elevation.
 there is your answer. If you want to be totally accurate anally so take into account the earths rotation at your co-ordinates. By the way if you drop a bullet from your bbl assuming this is an absolutely flat plane the same time elapses between the fired bullet and the dropped bullet. However there is no true flat plane on earth as it is an elongated sphere.Whacko Chuckle..... these things drive me nuts at ranges past 1000 yards.Big Grin
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Kickboxer Quote  Post ReplyReply Direct Link To This Post Posted: February/08/2012 at 13:49
Dale, I found this for you...
 

Multiplication by 0, 1, 2 and 3

In the next several lessons we will learn the basic multiplication facts.

Multiplying by 0

Any number multiplied by 0 equals 0.

Multiplying by 1

Any number multiplied by 1 equals that number.

Multiplying by 2 and 3

TWO
 0 * 2 = 0  1 * 2 = 2  2 * 2 = 4  3 * 2 = 6  4 * 2 = 8
 5 * 2 = 10  6 * 2 = 12  7 * 2 = 14  8 * 2 = 16  9 * 2 = 18
THREE
 0 * 3 = 0  1 * 3 = 3  2 * 3 = 6  3 * 3 = 9  4 * 3 = 12
 5 * 3 = 15  6 * 3 = 18  7 * 3 = 21  8 * 3 = 24  9 * 3 = 27

 




 

Multiplying by zero
Free lesson plan from HomeschoolMath.net

         

Five columns, each has zero giraffes.

0 + 0 + 0 + 0 + 0 giraffes.

5 × 0 = 0 + 0 + 0 + 0 + 0 = __

 

Zero  rows  - no rows of five giraffes. 

__ giraffes

0 × 5 = 0

 

Take three jumps of zero steps.  
Where do you end up?   
3 × 0 = 0.
 
 
 
Take ZERO or no jumps 
of three steps:  
0 × 3 = 0.


(no jumps)

 

Remember, multiplication by a whole number is REPEATED ADDITION. 
 

How many
 times we add

What number
we add

4

×

0

=

 0 +  0 + 0 + 0  =  0

Add 0 four times.
 

How many
 times we add

What number
we add

0

×

4

=

 (nothing to add) = 0

'Add' 2 zero times.
 
 
 
0 + ANY NUMBER = THAT NUMBER,
0 + X = X
0 + 0 = 0
 
Any number subtracted from itself = 0
 
X-X = 0
 
Simply from the RULES OF ARITHMETIC:
 
0*X = (0+0)X
0*X = (0*X) + (0*X)
(0*X) - (0*X) = (0*X)
(don't forget, any number subtracted from itself equals 0) THEREFORE;
 
0 = (0*X)
0=0
Basic math, no ring theory required. 
 
 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: February/08/2012 at 16:15
where do you think they get the rules of arithmetic--- the internet purplecow.math?
every example you gave comes from operations in ring theory and set theory--- it takes priority
do you think the AMS (american math society) takes proofs from giraffemath?
I was suprized however that you didn't start with something like -- Let Z contain all the sets of real numbers--- your arguement (and the beginning ofmine) doesn't even rule out imaginary numbers or extent the rings to exponential functions.
 
basic math comes from group, and number theory please do a little more in depth
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Kickboxer Quote  Post ReplyReply Direct Link To This Post Posted: February/08/2012 at 17:12
Originally posted by Dale Clifford Dale Clifford wrote:

where do you think they get the rules of arithmetic--- the internet purplecow.math?
every example you gave comes from operations in ring theory and set theory--- it takes priority
do you think the AMS (american math society) takes proofs from giraffemath?
I was suprized however that you didn't start with something like -- Let Z contain all the sets of real numbers--- your arguement (and the beginning ofmine) doesn't even rule out imaginary numbers or extent the rings to exponential functions.
 
basic math comes from group, and number theory please do a little more in depth

Dale, ring theory was derived from the basics of mathematics... not the other way around.  Fermat had an idea of the concept of "rings", but the theories were not popularized until the mid to late 1800's.  You don't need ring theory to prove -1*x = -x.  You do, however, need an understanding of the basic proofs to take on ring theory... effectively.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Urimaginaryfrnd Quote  Post ReplyReply Direct Link To This Post Posted: February/08/2012 at 20:29
My bullet would travel all the way to the deer  -- then it would hit the ground.

"Always do the right thing, just because it is the right thing to do".
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dsr Quote  Post ReplyReply Direct Link To This Post Posted: February/08/2012 at 20:38
Originally posted by Urimaginaryfrnd Urimaginaryfrnd wrote:




My bullet would travel all the way to the deer  -- then it would hit the ground.


What would hit the ground the bullet or the deer? And great now we get to fight over the variable "deer" ~ assume the deer is a sphere.....
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Alan Robertson Quote  Post ReplyReply Direct Link To This Post Posted: February/08/2012 at 21:23
Originally posted by dsr dsr wrote:

Originally posted by Urimaginaryfrnd Urimaginaryfrnd wrote:




My bullet would travel all the way to the deer  -- then it would hit the ground.


What would hit the ground the bullet or the deer? And great now we get to fight over the variable "deer" ~ assume the deer is a sphere.....
with a manifold...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: February/09/2012 at 08:01
Ah yes Fermat, to bad no one could find any of his proofs, to verify his claims of discovery. No doubt about the chronology of arithmetic the Sumarians used  to make their brew etc.  But its shortcomings were finally realized and a better method to do proofs, especially since they didn't work for -1*-1=1. did you show , that -1*-1 is not the same as -1^2, I missed it
Hint: Let Z be the set of all Real Numbers  etc.
 
The manifold and the deer/sphere analogy is really accurate. But its really a circle, sometimes with a bullseye on it. And the bench they shoot off is called a compacted stool.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Bigdaddy0381 Quote  Post ReplyReply Direct Link To This Post Posted: February/09/2012 at 08:18
compacted stool. Aint that what SVT gets on date night?
 
I should have sleep less in class...
 
 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SVT_Tactical Quote  Post ReplyReply Direct Link To This Post Posted: February/09/2012 at 08:40
I'm just waiting till they all get this equation figured out and then drop the bomb that what difference it makes when shooting over a body of water again!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: February/09/2012 at 10:36
fps must be converted to knots per hour
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dsr Quote  Post ReplyReply Direct Link To This Post Posted: February/09/2012 at 11:40
Originally posted by Alan Robertson Alan Robertson wrote:

Originally posted by dsr dsr wrote:

Originally posted by Urimaginaryfrnd Urimaginaryfrnd wrote:




My bullet would travel all the way to the deer  -- then it would hit the ground.


What would hit the ground the bullet or the deer? And great now we get to fight over the variable "deer" ~ assume the deer is a sphere.....
with a manifold...
 

Oh boy!    with a manifold --- hot gas --- internal ballistics ---

 

I myself prefer twister trousers (a type of manifold)

 



Edited by dsr - February/09/2012 at 12:00
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dsr Quote  Post ReplyReply Direct Link To This Post Posted: February/09/2012 at 12:25
Originally posted by Dale Clifford Dale Clifford wrote:

 
The manifold and the deer/sphere analogy is really accurate. But its really a circle, sometimes with a bullseye on it. And the bench they shoot off is called a compacted stool.
 

Being very politically incorrect the only thing I can think to say to that is EX-LAX  (see ICAO for LAX)

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: February/09/2012 at 12:39
hope your talking about airports and not Lax algebras, giraffes are over my head
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Bitterroot Bulls Quote  Post ReplyReply Direct Link To This Post Posted: February/09/2012 at 13:36
This thread looks like a crime scene.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dsr Quote  Post ReplyReply Direct Link To This Post Posted: February/09/2012 at 13:58
 
Originally posted by Dale Clifford Dale Clifford wrote:

hope your talking about airports and not Lax algebras, giraffes are over my head
 
Oh, thats good.

The hyperbolic nature of this thread leads us right back to here

Originally posted by Dale
Clifford Dale Clifford wrote:

...AMS (american math society) takes proofs from giraffemath?

And without further ado we leave the land of fruits and nuts.  (Again being very politically incorrect)  

 
 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Kickboxer Quote  Post ReplyReply Direct Link To This Post Posted: February/09/2012 at 16:21
dsr, I think your cheetah slowed down a bit...
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