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A references for common feats page?

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Bulletproof glass could be calced if you knew the tensile/shear strenght which is overall higher than normal glass because of the addition of layers of materials better suited for that kind of stress, sort of like concrete reinforced with rebar having a much better shear strenght than plain concrete.
 
I guess? Though, this wouldn't be fragmentation since it is just penatrating the glass rather than shattering it.
 
Maybe? I think you could find the PSI or MPa of the glass by figuring out the newtons of the bullet then the surface area. If say, the bullet hits with 4000 newtons on an area of 4 inches, it would be around 1000 newtons for every inch, or 224 PSI. Convert PSI to MPa to find J/cc which would lead to it's fragmentation energy.

Not exactly skilled with math or physics so this might be more than a little wrong
 
@Antvasima I'd wait until I finished the blog first.

Btw does anyone know the fragmentation, violent fragmentation and destruction values for plastic?
 
Finding the mechanical strength for all plastic is all but impossible. Plastic can range wildly in terms of strength and it is likely something that has to be calced on an individual basis.

Here is a website I found showcasing different mechanical strengths for plastic.

https://www.makeitfrom.com/
 
I'd mostly go for the strongest and most common forms, like Polycarbonate and PVC.
 
Well the layer of plastic for windshields is PVB, and mat web says it's tensile strength is 19.6 MPa. Shear strength is 0.577 of tensile strength.
 
I have asked DontTalkDT to help us out with this.
 
I was told to post evaluations of these calcs here. I will do so over time, that way I don't have to debate dozens of calcs at once.

Let me start with saying that when it comes to the page it should be listed where certain values are from and what is assumed. E.g. In the first calc, which vehicle is assumed and where is its weight from?

In that regards, global average weight seems to be 62kg. Possibly a better reference value than 70kg. ┬»\_(Òâä)_/┬»

That aside let's get into checking the calcs:

1. Vehicle Calc: Usually we for the most part assume that full KE of attacks scales for simplicity, but I suppose using momentum is fine here. It should be warned that calculating speed feats from momentum is usually not accepted (for the same reason as KE).

However in regards to the calcs logic: It says that it is assumed that the car sends the person flying. What is calculated is a perfectly inelastic collision, though. That means the formula holds exactly then if the person is not send flying, but instead is pasted onto the windshield of the car.

I think it is more or less the low-end assumption, though.

2. Human Falling: Seems fine. One should probably calculate how high a character has to fall from for that to apply.

Approximating that border without air resistance: 53 m/s / 9.8 m/s^2 = 5.4081632653061224s drop time.

r = (1/2)*a*t^2 gives the distance covered by such a long fall.

(1/2)*9.8*5.4081632653061224^2 = 143.316326530612242302 m

So one would have to drop about 143.3m before this calc gives the correct value, I believe.

3. Human shaped hole: What you want is the crossectional area, which is not half the surface area. This estimates cross-sectional area of a human as 0.68 m^2. Whether it is a very good estimation is quite debatable, though. If someone finds or calculates better estimates, that would be good.

Why 7/8th? That value seems to come out of nowhere. Not that it is an unreasonable value, it just seems kinda random.

Aside from that we should make note of the assumption that steel doors are at least as thick as the human is.
 
It's kind of important to know that not every human is very healthy though; that's why 62 kg is the average. Same with the average body temperature being 97.5 degrees fahrenheit being the average as opposed to 98.6 degrees fahrenheit being the healthy temperature.
 
I don't know. It is uncommon with so tiny people in fiction, unless they are women.

Maybe a few different standardised body weights for normal men, highly athletic men, and women would be better?
 
Well there is a difference between a 55 kilograms slim woman and a 110 kilograms highly athletic man.
 
But fiction always tends to show healthy-bodied adults taking the crashes and whatnot, so....

I suggest using both the average and healthy weights in that case.
 
Fair enough, but I want to hear DonTalk's thoughts. Though, of course if said character has an official weight, we use that.
 
Doesn't what is healthy weight depend on gender and height? Or is that some average of healthy weight?

Aside from that it depends on how many value we want to calculate. If we want to do two one could do both averages. One could probably also split ideal weight for man and woman.
 
Yeah, Healthy weight does depend on height and gender yes, and average height varies from country to country also.
 
That seems fine to me.
 
Okay. I suppose that we might have to remove it then.

I have similar concerns about the skyscraper calculation causing lots of problems, due to our members starting to assume that they can use it for any large building-wrecking feat.
 
No, that's not how the calc works. This calc assumes you use a basic building that qualifies to be a skyscraper, not a building that's larger than the average skyscraper itself. For those buildings we'll have to deal with different calcs.

For example, destroying the One World Trade Center is vastly different from blowing up the Empire State Building not only because of the structure and materials, but also because of the design itself.
 
I already know that feats such as melting a Skyscraper being calc'd at 7-A where as vaporizing one is Low 7-B makes it pretty cut and paste that it's flawed. Obviously heating the same object to the 3rd state of matter requires more energy than heating it to only the 2nd state. So we do need those calcs to be redone.

And I do remember the bullet proof calc being inflated; as being immune to handguns is only like a Wall level durability feat. And while the calc was done using some strangely composite bullet, the main part is that it should have had the volume of the bullet compared to a fist rather than the whole human body. Which would result in no more than Small Building level as opposed to City Block level.
 
I believe a .950 JDJ round was used, not a composite bullet. Although the speed of a .220 was used.
 
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