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If we made an absolutely sharp and absolutely durable knife, how much force would it take to stab through a slab of steel?
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>>13888970
0N.
Stupid question.
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>>13888972
Care to elaborate?
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>>13888970
12
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>>13889412
Nope
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>>13889412
If something was perfectly sharp to the molecular level itd cut through anything with incredible ease
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>>13889541
1 atom thick point still has resistance as it interacts with the surface of a material, just fewer interactions to handle to push through
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>>13888972
nah, even if you needed no force to separate atoms on the point of the knife, you would need some to deform the steel when entering it
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>>13889412
>>13889546
>>13889565
If it was both perfectly sharp and perfectly durable, then steel cannot have any effect on the knife. Why?
If the knife slowed down, then it's not absolutely sharp. If the knife maintained the same speed but was damaged, then it's not absolutely durable.
If you demand interactions at the atomic level, then you must remove the conditions of either absolute sharpness and absolute durability.
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>>13889699
>If the knife slowed down, then it's not absolutely sharp
I don't really see why this is a condition. Maintaining absolute sharpness and durability would only require that the knife's own atoms maintain their relative positions without fail.
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>>13889699
Define absolutely sharp. How do you sharpen a knife to sharper than one atom thickness?
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>>13889778
>>13889779
>Define absolutely sharp
Vanishing surface area, so the pressure produced by a unit of force is infinite.
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>>13889876
Then by definitely 0, but there's no way to achieve that and it isn't even a realistic statement given the knife is made out of matter and not dark matter or neutrons or something else that would barely interact with a metal surface
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>>13889876
The edge still has to be one atom wide, so it can't be infinite.
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>>13889885
Yes. That's why I said it's a stupid question.
>>13889906
Then it's not absolutely sharp.
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>>13889911
Then please just delete the thread
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>>13888970
>inb4 1 atom wide: the only bond which allows this is ionic but it would be extremely fragile as it's a single atom
also, steel can be CCC or CFC depending on temperature, what you need is a knife smaller than an interstitial space in the reticle, so a knife made of hydrogen would easily rip through the sheet as it's way smaller than iron.
Technically the correct answer is 0, but this only if the atoms don't interact with eachother
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none at all
you never said my imaginary knife was disallowed
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>>13888970
This has already been answered by material science. The studies began with theories of machining (cut) metals with lathes, shapers and milling machines. And of course the military studies how to pierce through big metal and ceramic plates with explosives and sharp metal bars.
So read a book nigger.
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>>13888970
This is a trick question.
A weapon even with max upgrades can't interact with inanimate objects in the environment.
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>>13888970
The knife in this scenario isn’t even relevant if it’s infinitely sharp and durable. You simply exclude the penetrator from your yield calculations and only look at the force applied to the slab of steel.
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>>13888970
It wouldn't 'stab' through the steel at all. It would melt while still remaining solid(like a fluid under immense pressure is) and merge with it, assuming the knife is also steel. You wouldn't be able to pull it out once its in.

When two physical objects make contact, their atoms don't touch: they are mostly empty-space. What you have are electron fields that are the same charge and so repel each other. 'Sharpness' in this context is simply referring to minimising the interaction between two different electron fields. As the scenario stipulates that the knife has 'absolute' durability, it's electron field must also be over-coming that of the slab to accommodate this magic-rule.

The energy for this bonding process(a chemical change) would come from the same place the knife's durability does: The Invisible Penis Dimension
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Would eagle eyes identify the bayonet 4me?
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>>13890266
Swiss Model 1918
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>>13891560
Thank
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>>13889426
Litres or volts?
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>>13890266
>>13891560
https://www.youtube.com/watch?v=hZXbOVVIBjg&ab_channel=BigBrother
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>>13890074
with this logic any two sheets of metal would bond to each other
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>>13889906
>The edge still has to be one atom wide
There are weird forms of matter which only exist in special conditions (like at the heart of a neutron star) which are less than an atom wide.

Let's say you have a black hole knife.
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>>13888970
as much energy as it would take to break the bond between two iron atoms per atom thickness. so dE/dx gives you force.
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>>13892121
Cool! In Beavis voice.
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it's all about surface area and that just requires pressure
anyway the real question is how fast it needs to be moving
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>>13894075
No, you retard. There are no sheets of metal that are absolutely durable and absolutely sharp.
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>>13894075
You can weld together planks metal with an explosive to press them together super hard. Just putting them together doesnt work, no matter how flat they might be. I dont know why, could be because steel is made of many individual crystals and theres a mismatch? The crystals are probably messed up near the surface, its said that solid properties at the surface are different than inside a crystal, because the surface just cuts the crystal and that changes all the force balance?



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