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Not only that, the explosion has to be at least 13 km/s fast like the OP says, MINIMUM.
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Cook's Edit to Taylor's Formula
- Thread starter Arc7Kuroi
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ok then my calculation is fine
Since it is similar to another Bomb(in power and how it works) in the verse which is literally 200+km/s
(Ofc I don’t use the 200+km/s in the other calculation that’s calc stacking just to say short timeframe is makes sense)
Thx
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Well, we better wait for DT then, he'd know how to write up a paragraph.
And this formula should be separate from the other formulas, as in, Cook's formula should have its own paragraph separate from the other explosion calculation methods while listing down all the prerequisites needed to be able to use this formula. Prolly also explain that it works in outer space.
And this formula should be separate from the other formulas, as in, Cook's formula should have its own paragraph separate from the other explosion calculation methods while listing down all the prerequisites needed to be able to use this formula. Prolly also explain that it works in outer space.
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Honestly, I don't see how. I don't even see how they would want to use it for supernovas.
The inherent problem is that space is (more or less) a vacuum and shockwave formula hence never works. 'cause, which medium does the shockwave even travel through?
And this isn't just me rambling about theoretical problems either. Like, look at the formula. It literally has the atmospheric density in it, as the variable p_0. If you use that in space p_0 = 0. So you multiply by 0, making the energy 0. Something's obviously wrong there.
I assume when the article says it helps with supernova, then it means after putting a lot more math and consideration into the subject.
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WELL SHIT.
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Technically rho isn’t 0 in space especially near stars, star clusters, nebulae, solar systems, galaxies, etc. Contrary to what high school would teach you, space is not a perfect vacuum. <- This isn’t supposed to be condescending lol
However, while the formula was made with x, y, and z in mind it’s only been tested accurate with high speed large explosives, which is what we should keep it to.
When I say “hypothetically it should also work for blah blah”, I say that because it was made to be a more broad formula. But that doesn’t mean it necessarily is, and has only been tested with your classic big bombs.
However, while the formula was made with x, y, and z in mind it’s only been tested accurate with high speed large explosives, which is what we should keep it to.
When I say “hypothetically it should also work for blah blah”, I say that because it was made to be a more broad formula. But that doesn’t mean it necessarily is, and has only been tested with your classic big bombs.
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I mean, that's why I said more or less vacuum. The density of the interplanetary medium is like 5 particles per cm^3, which probably works out to an atmospheric density of like 8.3677875*10^-24 g/cm^3 (Assuing hydrogen particles... I think it's probably plasma). That's very near 0 and I can't imagine that those few particles actually dominate the shockwave propagation.
My speculation is that they either consider the shockwave propagation through the exploding star itself or take into account how the exploding star's matter would spread during the explosion. Or they just use a similar idea, but adjust it for supernova to include photons and particles being launched and stuff. Idk.
Aaaaanyway, I will try to get something posted on the explosion yield page soon.
My speculation is that they either consider the shockwave propagation through the exploding star itself or take into account how the exploding star's matter would spread during the explosion. Or they just use a similar idea, but adjust it for supernova to include photons and particles being launched and stuff. Idk.
Aaaaanyway, I will try to get something posted on the explosion yield page soon.
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Ok, sooooooo... I was about to edit in that section for the formula when I thought: Should I really insert information from an article which physics I don't understand without making sure that it is written or reviewed by anyone credible?
So I did that and... I'm not sure anymore I want to include it without someone either explaining the physics to me or a second source to support it.
Like, for a start that's from a website where everyone can publish and it isn't reviewed. That's in itself not that bad, if it's just a copy of something that can be assumed to be correct.
Next, I googled that dude's name... nothing except publishing stuff at this and similar sites. So he probably isn't a Prof. and possibly not a doctor or anything either. Those would usually have published at least one scientific paper somewhere credible (given, it's possible I just didn't find it. Then again, he doesn't actually call himself with a title, so I assume he has none).
I also googled the article title and some short quotes from it to see if it's published on any credible side... nope.
Then I looked at other stuff he published. And well, this and this just don't scream credible source at me. It sounds like he has some... unusual ideas.
So I did that and... I'm not sure anymore I want to include it without someone either explaining the physics to me or a second source to support it.
Like, for a start that's from a website where everyone can publish and it isn't reviewed. That's in itself not that bad, if it's just a copy of something that can be assumed to be correct.
Next, I googled that dude's name... nothing except publishing stuff at this and similar sites. So he probably isn't a Prof. and possibly not a doctor or anything either. Those would usually have published at least one scientific paper somewhere credible (given, it's possible I just didn't find it. Then again, he doesn't actually call himself with a title, so I assume he has none).
I also googled the article title and some short quotes from it to see if it's published on any credible side... nope.
Then I looked at other stuff he published. And well, this and this just don't scream credible source at me. It sounds like he has some... unusual ideas.
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TLDR it starts with Taylor’s Formula which began as dimensional analysis, and uses government releases data, along with lab testing to critique and make the formula more precise. But I can look for some scholarly articles if you’d like and go into more detail if you’d like.
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Like, as far as Taylor's formula goes I'm ok. I can derive that myself.
It's the rest I'm not sure about. If you can find some second source for that constant, that would be great.
Edit: Or you can explain it in more detail. Personally I get unsure at the point he starts introducing U, since I'm not sure if those relations he just puts down actually make sense or not.
It's the rest I'm not sure about. If you can find some second source for that constant, that would be great.
Edit: Or you can explain it in more detail. Personally I get unsure at the point he starts introducing U, since I'm not sure if those relations he just puts down actually make sense or not.
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Ouch.
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i think you forgot now 
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Wait hold up, is your only issue the stuff involving U?
U is just a velocity. They're basically just doing substitutions, like Cook's Eqn is proportional to (R^5)/(t^2), which can be rewritten as (R^3)*(U^2) or M*U^2 (because mass is proportional to R^3). But the reason they even bring up U is to derive a relationship for the time of arrival for shockwaves. It doesn't have anything to do with the actual explosion formula. AKA the U stuff is irrelevant, if you get everything before it, that's all you need.
Sorry this took me so long...
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It's not just U in itself. It's just the derivation in total.
Why can he in the following describe gamma the way he does?
And is E_fireball different than E_total? If so, why is E_fireball = E_kinetic * (E_total/E_kinetic)?
And why is E_kinetic = P*V. What is P even? He says P is pressure, but... which pressure? Of what? When?
Why can he in the following describe gamma the way he does?
And is E_fireball different than E_total? If so, why is E_fireball = E_kinetic * (E_total/E_kinetic)?
And why is E_kinetic = P*V. What is P even? He says P is pressure, but... which pressure? Of what? When?
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"The total fireball energy (E_fireball)"
It's E_total.
You're talking about the part where he derives the time of arrival, this isn't part of the fireball yield derivation, it isn't actually relevant to the explosion yield formula derived.
It seems like a lot of your confusion is regarding stuff that isn't actually a part of the explosion yield formula's derivation. Out of your questions, the only part relevant to the actual formula in question is your question about gamma. To which gamma is just the heat capacity ratio (Cp/Cv).
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bump
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Weird, but ok.
No? I don't think so?
The formula for the energy he derives comes from rearranging equation 10.
Equation 10 is the result of equation 9 and equation 4.
Equation 9 is based on equation 8.
Despite what he wrongly writes (again, I think I have a good reason not to trust this) 8 isn't the result of 8 and 6, but seems to follow from equation 7 and equation 5. (Equation 8 also has a typo, in that the left side has an A too many)
Equation 7 supposedly follows from 5 and 7, which also seems wrong. Then again, not sure what it actually follows from this time. Probably equation 6 somehow, as that seems to be used nowhere else.
In any case, equation 4 is based on substituting 1 and 3 into 2 apparently.
And my questions relate to equation 2.
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Add "Where does Equation 7 come from" on my list of questions btw...
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ı see...
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What does each variable in this formula stand for, by the way? I'm not sure.
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Equation 8 is based on 7 and 5, there is a typo there yeah.
Equation 7 comes from U = BR/t where R = At^(2/5), subbing in R, U = BAt^(2/5)/t = ABt^(-3/5)
Plugging in Equation 1 into 2 gets us (2/3)pi*R^3*rho*U^2/(gamma-1), subbing Equation 3 into that gets us (2/3)*pi*R^5*rho*B^2/(t^2(gamma-1)), which checks out with what he wrote for Equation 4
Ek = P*V is just pressure times volume, where the pressure is of an ideal gas (treating our atmosphere as such).
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If we're assuming an ideal gas, wouldn't E_k = 3/2*P*V be the case instead, if E_k refers to the kinetic energy of the molecules?
And if this is supposed to be the equation for the kinetic energy of the molecules in an ideal gas, how is that equal to 1/2*M*U^2 with U being the outward blast velocity?
Talking about U, he asserts the following:
And if this is supposed to be the equation for the kinetic energy of the molecules in an ideal gas, how is that equal to 1/2*M*U^2 with U being the outward blast velocity?
Talking about U, he asserts the following:
How does he prove the idea that it deceleration happens at a constant rate? I had the pleasure of looking into how the U.N.'s calculator for explosions calculates shockfront velocity for when I wrote the explosion dodging feats stuff. The formula they use is... complicated. Let's just say it involves a 14th degree polynomial and some other stuff. It was definitely not changing at a constant rate in any case.
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