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My Hero Academia: The Final Smash Calculation

The shockwave reaches america, both the cross sectional area of a half sphere and cylinder are a circle and both would be the same value (a shockwaves at ground level expands as a half sphere, cloud formations expand in a cylinder hence the two versions) its the total distance of the shockwaves because doing otherwise for the initial would be incorrect here for how this calc works
Sorry, I meant what was the value and the formula used to get 67428900 meters^2?
 
I'll just steal Clover's rq and edit the timeframe for 1 hour vs 5

v_f = 29640.80 - (0.0042975296 * 3600) = 29625.3288934 m/s

29640.80 - (0.0042975296 * 18000) = 29563.4444672m/s
Sorry, I meant what was the value and the formula used to get 67428900 meters^2?
The distance from mount fuji to America just and the shapes and reasoning I gave
 
The distance from Mt. Fuji to America per Rusty's calc is 10731640 m.

I'm just a bit confused on how you turn that figure into 67428900 m^2.
Yeah going back over the math I'm actually not sure what happened there but somehow I used the 29640.80m instead of that since now I'm getting 90452811936151m^2 which ofc is vastly different from before so I'm actually not sure what happened
 
Yeah going back over the math I'm actually not sure what happened there but somehow I used the 29640.80m instead of that since now I'm getting 90452811936151m^2 which ofc is vastly different from before so I'm actually not sure what happened
Doing that gets me a negative number for the final velocity, so I have no idea what's going on anymore
 
Doing that gets me a negative number for the final velocity, so I have no idea what's going on anymore
Well, if we ignore that negative symbol for a second and plug it in it would put Deku at 1.43190249858E30 Joules or 342 Exatons of TNT with base OFA (MOON LEVEL) and up to 5x times higher with the quintuple smash at 7.15951249291E30 Joules or 1.7 Zettatons of TNT (SMALL-PLANETARY LEVEL).
 
Well, if we ignore that negative symbol for a second and plug it in it would put Deku at 1.43190249858E30 Joules or 342 Exatons of TNT with base OFA (MOON LEVEL) and up to 5x times higher with the quintuple smash at 7.15951249291E30 Joules or 1.7 Zettatons of TNT (SMALL-PLANETARY LEVEL).
So what I'm basically saying is we should totally just go ahead with this, no further questions need to be asked.
 
Doing that gets me a negative number for the final velocity, so I have no idea what's going on anymore
Also I just checked and you can get a negative number out of that kinematic equation if the acceleration is negative, which it is since it's deceleration. So as far as I can tell, Small-Planetary Deku actually works.
 
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Well, if we ignore that negative symbol for a second and plug it in it would put Deku at 1.43190249858E30 Joules or 342 Exatons of TNT with base OFA (MOON LEVEL) and up to 5x times higher with the quintuple smash at 7.15951249291E30 Joules or 1.7 Zettatons of TNT (SMALL-PLANETARY LEVEL).
Dude this is a Calc members only thread

You can't comment here unless you get accepted to
 
What were the errors with it??
I didn't say there were errors in it, it's just that it likely hasn't been brought up in the thread because it hasn't been evaluated and until it's been evaluated and accepted it shouldn't be considered yet.
 
I didn't say there were errors in it, it's just that it likely hasn't been brought up in the thread because it hasn't been evaluated and until it's been evaluated and accepted it shouldn't be considered yet.
Why does no one consider or even look at it then?
 
This better?

Volume = 3.6181125e+14 * 21336 = 7.7196048e+18 meters^3

Density = 0.5258 kg/m^3

Mass = 7.7196048e+18 * 0.5258 = 4.0589682e+18 kg

The air moved out in a cylindrical motion so I'll use a cylinder.

Drag Coefficient = 1.12 (between 1.08 and 1.16 from what I found)

Cross-Sectional Area = 3870756308488 meters^2 (This time using the diameter of typhoon tip instead of the distance from USA to Mount Fuji, this should be consistent the Therefir's

0.5 * 0.5258 kg/m^3 * (29640.80 m/s)^2 * 1.12 * 3870756308488m^2 = 1.00134626e+21 N

a = 1.00134626e+21N / 4.0589682e+18kg = 246.699706 m/s^2 (It's negative because it's deceleration)


We'll use the time it takes the shockwave to travel the diameter of Typhoon tip for our time below
1110000m / 29640.80m/s = 37.448382s



v_f = v_i + a*t

v_f = 29640.80m/s - (246.699706 m/s^2 * 37.448382s) = 20402.2952m/s

KE = (1/12) * 4.0589682e+18 * 20402.2952^2 = 1.4079669e+26 Joules or 33.651216 Petatons of TNT
 
Truth be told I don't think this formula actually tackles the root issue that I brought up, though I appreciate the explanations and I'm trying to work through the problem.
No problem but this is as close as you'll get because otherwise there's nothing else ya could do to get closer to tackle it as this would be the most accurate to what it is you're wanting and it does significantly reduce the speed from the 29640 as well as still acts as omnidirectional KE with the 1/12 KE formula already taking into account the air moving at the edge is slower than air moving in the center. So while not exactly how you want it this would be the most accurate version of the calc regardless as there's no real math or studies YET that we can find at least that is able to take into account exactly what you're wanting to a T
 
This better?

Volume = 3.6181125e+14 * 21336 = 7.7196048e+18 meters^3

Density = 0.5258 kg/m^3

Mass = 7.7196048e+18 * 0.5258 = 4.0589682e+18 kg

The air moved out in a cylindrical motion so I'll use a cylinder.

Drag Coefficient = 1.12 (between 1.08 and 1.16 from what I found)

Cross-Sectional Area = 3870756308488 meters^2 (This time using the diameter of typhoon tip instead of the distance from USA to Mount Fuji, this should be consistent the Therefir's

0.5 * 0.5258 kg/m^3 * (29640.80 m/s)^2 * 1.12 * 3870756308488m^2 = 1.00134626e+21 N

a = 1.00134626e+21N / 4.0589682e+18kg = 246.699706 m/s^2 (It's negative because it's deceleration)


We'll use the time it takes the shockwave to travel the diameter of Typhoon tip for our time below
1110000m / 29640.80m/s = 37.448382s



v_f = v_i + a*t

v_f = 29640.80m/s - (246.699706 m/s^2 * 37.448382s) = 20402.2952m/s

KE = (1/12) * 4.0589682e+18 * 20402.2952^2 = 1.4079669e+26 Joules or 33.651216 Petatons of TNT
No problem but this is as close as you'll get because otherwise there's nothing else ya could do to get closer to tackle it as this would be the most accurate to what it is you're wanting and it does significantly reduce the speed from the 29640 as well as still acts as omnidirectional KE with the 1/12 KE formula already taking into account the air moving at the edge is slower than air moving in the center. So while not exactly how you want it this would be the most accurate version of the calc regardless as there's no real math or studies YET that we can find at least that is able to take into account exactly what you're wanting to a T
For now I'll see what the others think as well about it as well
@TheRustyOne @Therefir @CloverDragon03

Thoughts on this version of it
 
No problem but this is as close as you'll get because otherwise there's nothing else ya could do to get closer to tackle it as this would be the most accurate to what it is you're wanting and it does significantly reduce the speed from the 29640 as well as still acts as omnidirectional KE with the 1/12 KE formula already taking into account the air moving at the edge is slower than air moving in the center. So while not exactly how you want it this would be the most accurate version of the calc regardless as there's no real math or studies YET that we can find at least that is able to take into account exactly what you're wanting to a T
I think the issue with the method you've brought up is that it is calculating the drag force on it as if were a fixed object over the entire timeframe, with the mass, the volume, the area, etc. all being constant variables. Since the shockwave is constantly expanding, making all of those things to be unchanging doesn't produce an accurate result.
 
Since the shockwave is constantly expanding, making all of those things to be unchanging doesn't produce an accurate result.
I mean it does take into account that it isn't obviously just the storm mass that's moving considering we're doing the air with this and the drag does slow it by about 9000m/s and again the KE formula we implore does take into account varying speeds already. The timeframe ya can't really adjust in this regardless not without creating your own new formulas but otherwise the drag part literally uses the mass to account for deceleration by a wide margin


this calc is quite literally saying the speed was 29000m/s with its initial velocity but due to x amount of mass its affecting over this amount of distance and this time it that the speed is now reduced by 9000m/s and still varies regardless which the KE takes into account idk I'll just leave it to others
 
Air density with clouds these thick and high up will change drastically. The clouds are 8304.80 m above sea level and are 21336 m thick, the total is 29640.8 meters. The half way point of the effect area is 14820.4 m above sea level. This is basically 15000 m, which has an air density of 0.1948 kg/m^3.

We use the cloud calculator because it's able to calculate the different density levels to get a weight that is far more accurate.

Look at the weight you're getting here. 4.0589682e+18 kg is over 3.3x higher than what the actual cloud calculator got with the exact same volume of air. The weight would be lower, but the speed would become higher as less density would mean less air resistance.

I also don't see this as more accurate than my or Therefir's original calculation in the OP. To explain myself.

The initial speed of the shockwave, at least when it begins splitting, is 29640.80 m/s.

One week later, we're told that strong winds are still expecting to be felt in the USA, and is confirmed to have been caused by Izuku. Occam's Razor tells us the simplest answer is the most likely one, considering how the story is written, I'm far more likely to believe Izuku's shockwave is still moving even after one week later.

While I completely accept the idea that air resistance did slow it down, I don't accept any idea that it was significant enough to effect my calculation above. As I said above, even if only 1 percent of that wind speed was caused by Izuku's shockwave. Which is incorrect, because it's noticeable enough that the weather report can tell.

The difference of wind speed by the time it reaches the USA is negligible, it will always be negligible because of that detail.

The fact Izuku's shockwave is STILL producing strong winds one week later shuts down any idea that the deceleration was significant.

Note: The calculation is NOT assuming the wind speed at seal level was that fast. The wind speed above was clearly faster than the wind speed from below. Or else all of Japan and even America would've been destroyed. I'm only measuring the wind speed from over 8000+ meters above sea level. Which means any damage produced would be very minimal, as the vast majority of the energy is in the skies above. This is why I'm actually a bit against using the Inverse Square Law here.

Considering all of these facts, no one has brought up any evidence that suggest to me that the initial speed of the shockwave would slow down massively enough to make my calculation inaccurate. The reasoning above are just over complications to something very simple.

To give an example. Let's say by the time the shockwave reached America, it decelerated to half speed as the initial shockwave.

Initial Speed = 29640.80 m/s and Final Speed = 14820.4 m/s

Distance = 10731640 meters.

Deceleration would be -30.70 m/s^2.

If this was true, the final velocity for Izuku's shockwave after just one day would be -2622839 m/s.

Which is obviously incorrect, this deceleration would mean the shockwave would've disappear. This contradicts the series, his shockwave still exist even after one week has passed. And as I said above, no one here has provided explanation to say that the strong wind wasn't caused by Izuku's air pressure.
 
Air density with clouds these thick and high up will change drastically. The clouds are 8304.80 m above sea level and are 21336 m thick, the total is 29640.8 meters. The half way point of the effect area is 14820.4 m above sea level. This is basically 15000 m, which has an air density of 0.1948 kg/m^3.

We use the cloud calculator because it's able to calculate the different density levels to get a weight that is far more accurate.

Look at the weight you're getting here. 4.0589682e+18 kg is over 3.3x higher than what the actual cloud calculator got with the exact same volume of air. The weight would be lower, but the speed would become higher as less density would mean less air resistance.

I also don't see this as more accurate than my or Therefir's original calculation in the OP. To explain myself.

The initial speed of the shockwave, at least when it begins splitting, is 29640.80 m/s.

One week later, we're told that strong winds are still expecting to be felt in the USA, and is confirmed to have been caused by Izuku. Occam's Razor tells us the simplest answer is the most likely one, considering how the story is written, I'm far more likely to believe Izuku's shockwave is still moving even after one week later.

While I completely accept the idea of air resistance did slow it down, I don't accept any idea that it was significant to effect my calculation above. As I said above, even if only 1 percent of that wind speed was caused by Izuku's shockwave. Which is incorrect, because it's noticeable enough that the weather report can tell.

The difference of wind speed by the time it reaches the USA is negligible, it will always be negligible because of that detail.

The fact Izuku's shockwave is STILL producing strong winds one week later shuts down any idea that the deceleration was significant.

Note: The calculation is NOT assuming the wind speed at seal level was that fast. The wind speed above was clearly faster than the wind speed from below. Or else all of Japan and even America would've been destroyed. I'm only measuring the wind speed from over 8000+ meters above sea level. Which means any damage produced would be very minimal, as the vast majority of the energy is in the skies above. This is why I'm actually a bit against using the Inverse Square Law here.

Considering all of these facts, no one has brought up any evidence that suggest to me that the initial speed of the shockwave would slow down massively enough to make my calculation inaccurate. The reasoning above are just over complications to something very simple.

To give an example. Let's say by the time the shockwave reached America, it decelerated to half speed as the initial shockwave.

Initial Speed = 29640.80 m/s and Final Speed = 14820.4 m/s

Distance = 10731640 meters.

Deceleration would be -30.70 m/s^2.

If this was true, the final velocity for Izuku's shockwave after just one day would be -2622839 m/s.

Which is obviously incorrect, this deceleration would mean the shockwave would've disappear. This contradicts the series, his shockwave still exist even after one week has passed. And as I said above, no one here has provided explanation to say that the strong wind wasn't caused by Izuku's air pressure.
That's all good that was just my attempt to kinda match Damages concerns but I otherwise am still partial to the your and Therefir calcs
 
The initial speed of the shockwave, at least when it begins splitting, is 29640.80 m/s.

One week later, we're told that strong winds are still expecting to be felt in the USA, and is confirmed to have been caused by Izuku. Occam's Razor tells us the simplest answer is the most likely one, considering how the story is written, I'm far more likely to believe Izuku's shockwave is still moving even after one week later.
I think this is a misue of Occam's Razor. Assuming the Izuku's shockwave maintained a constant speed over the entire distance actually adds complexity by ignoring the physics involved (shockwaves should slow down at they propagate through the atmosphere). A simpler explanation to me would be that the after-effects of Izuku's punch at just the result of residual turbulence his punch caused, not his shockwave still travelling. Also, if you attribute all of the energy of the wind over the entire week to just Izuku's punch, then that would mean that the air would've been at a complete standstill otherwise.

While I completely accept the idea that air resistance did slow it down, I don't accept any idea that it was significant enough to effect my calculation above. As I said above, even if only 1 percent of that wind speed was caused by Izuku's shockwave. Which is incorrect, because it's noticeable enough that the weather report can tell.

The difference of wind speed by the time it reaches the USA is negligible, it will always be negligible because of that detail.

The fact Izuku's shockwave is STILL producing strong winds one week later shuts down any idea that the deceleration was significant.
You assume it has a neglible effect due to the effects of Izuku's punch still being present a week later but that doesn't justify assuming the initial speed was maintained the whole distance. Air resistance slows down shockwaves, especially over long distances. I don't deny that the effects of Izuku's punch still reached the USA, but as the video of the volcano showed just because you're "within the shockwave radius" doesn't mean that the edges of the shockwave were as badly affected as the epicenter of the shockwave.

The only thing the events a week later really tells us is that there is a lingering atmosphere effect from Izuku's punch; it doesn't tell us that the shockwave crossed the entire distance with the same speed.

Considering all of these facts, no one has brought up any evidence that suggest to me that the initial speed of the shockwave would slow down massively enough to make my calculation inaccurate. The reasoning above are just over complications to something very simple.
The burden of proof would be on the person claiming that the entire 1210897470122445800 kg mass of air moved at 29640.8 m/s. That's the positive claim in this scenario.

What you've done is estimate that a significantly smaller mass of air moved 29640.8 m/s as a result of the shockwave, and then you've extrapolated that speed to be used for the entire volume of air in a cylinder extending to the US with Mt. Fuji at its center just because we know the effects of the shockwave reached that far.

Like... I fail to see how this isn't being noticed as a flaw. The effects of the shockwave reached the US, so you assume all of the air between Mt. Fuji and the US to have moved with the same speed as the initial velocity?

To give an example. Let's say by the time the shockwave reached America, it decelerated to half speed as the initial shockwave.

Initial Speed = 29640.80 m/s and Final Speed = 14820.4 m/s

Distance = 10731640 meters.

Deceleration would be -30.70 m/s^2.

If this was true, the final velocity for Izuku's shockwave after just one day would be -2622839 m/s.

Which is obviously incorrect, this deceleration would mean the shockwave would've disappear. This contradicts the series, his shockwave still exist even after one week has passed.
Your reasoning is flawed in assuming constant deceleration but that's not really how a constantly expanding shockwave would decelerate. Besides that, you're assuming that just because the shockwave itself decelerates that means that there wouldn't be any after-effects felt later on, but as I mentioned above that's not necessarily true. Even after the initial shockwave has passed, the weather can still suffer after-effects and turbulence and that doesn't require the shockwave to have gradually slowed down over the course of a week to just normal wind speeds.
 
I think at this point it'd be better to let other calc group members say what they agree with or disagree with. For obvious reasons, I'll side with the majority rule.

If either of us could convince the other it would've happened by now, at this point I'd just be wasting all both of our time.

It'd probably help your points if you could figure out how to make a calculation of your own. However, I'm well aware you're busy and don't much time to do so.

Even though in my subjective opinion, I feel like your massively overcomplicating this, but that's all I'll say on the matter in this comment.
 
That seems reasonable - I'm open to listening to other Calc Group Member's views on it. For what it's worth I have contacted DontTalkDT for their input, who I think should be able to explain whether or not my point has any merit in the thread.

If I could think of an easy alternative to the calc in the OP I'd have made one already; but I will try coming up with an reasonable alternate method while waiting for other CGM's to comment.
 
I support TheRusty's point of view, the air density is so low at those altitudes, and the fact that the shock wave was able to reach the US in such a short time, makes me think that the velocity loss is so negligible that trying to calculate would be a waste of time.

Looking at all the calculations, all of them have merit and are based on some statement, and although using my calculation would be the simplest and "safest" way, since it ignores what happened in the US, really any of the calculations are fine depending on how you interpret the facts.

If I have to choose, I would like to go with my calc of course, but I wouldn't be against using the other calcs.
 
I support TheRusty's point of view, the air density is so low at those altitudes, and the fact that the shock wave was able to reach the US in such a short time, makes me think that the velocity loss is so negligible that trying to calculate would be a waste of time.
As far as I'm aware we don't have explicit confirmation on how long it took to reach the US, right? I know Rusty's calc calcs it to be around 6 minutes but that's by assuming constant speed.
 
As far as I'm aware we don't have explicit confirmation on how long it took to reach the US, right? I know Rusty's calc calcs it to be around 6 minutes but that's by assuming constant speed.
Well tbf I brought it up before but a similar shockwave caused by a much weaker irl event only took a little over an hour to traverse the entire earth (granted the means causing it were different) so like I can't imagine this taking more than an hour tops even if we're really really wanting to lowballing it. We know at least for that entire week its been affecting america and cleared the weather there so it regardless got there the exact same day
 
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