Right, I was just saying I wonder what the atomic dynamic of that whole thing really is when those bonds between the molecules are broke; the thermodynamic ( if you could call it that ) portion was just my bet on what happens--just makes sense to me, lots of compression, lots of heat. I mean, what really happens to stuff when it's cut... I think it's interesting to think about anyway.
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- Thread starter jgloveracob
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Right, I was just saying I wonder what the atomic dynamic of that whole thing really is when those bonds between the molecules are broke; the thermodynamic ( if you could call it that ) portion was just my bet on what happens--just makes sense to me, lots of compression, lots of heat. I mean, what really happens to stuff when it's cut... I think it's interesting to think about anyway.
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jgloveracob: It's one thing to be 15 and be curious, or post intelligent questions. It's another thing to be 15, get only a B in 10th grade chemistry, and come on to a forum stating incorrect conclusions as FACT.
Yes, it would be interesting to know exactly what happens at the molecular level. I've been trying to find some good info online but it's proving difficult.
Yes, it would be interesting to know exactly what happens at the molecular level. I've been trying to find some good info online but it's proving difficult.
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The downside of making declarations of 'fact', is that if you expect such a declaration to carry any weight of credibility, you actually have to PROVE IT AS FACT. Reading a textbook (apparently a high school textbook, in this case; we all know those are always right on the money), and then making sweeping generalizations based on what you INTERPRETED you read in the book, doesn't make fact of anything.
A former boss of mine had a very simple way of separating statements of fact, from mere conjecture. He only needed two words:
SHOW ME.
It's interesting how 'fact' is much, much more difficult to establish, once someone actually asks for proof.
A former boss of mine had a very simple way of separating statements of fact, from mere conjecture. He only needed two words:
SHOW ME.
It's interesting how 'fact' is much, much more difficult to establish, once someone actually asks for proof.
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Polished vs. Toothy
Some like polished, some toothy, But thats just their opinion right?
I sat down and thought about it today and thought I would add some FACT to the argument.
Well here is some NON biased FACTS about the edges.
words, words, words....
As well as insulting people that call you on the fallacy of confusing one for the other. Humility is a more robust skill than text book speculation/memorization.
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Sorry guys, Been having a bad day today. I'm calm now. But back to the subject. I'm trying to say that the electrons on the edge are repelling the electrons on the material resulting in a cut. If this isn't the case please tell me in a serious manner why it isn't correct.
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I'm just a chemist moonlighting as a materials engineer, so this is a bit out of my field, but I'll take a stab at it.
Because electrons alone are not what is holding the material together. You are actually dealing with molecular bonds between atoms. So you need to look at bond strengths. Metal cuts plastic because the metal is a crystal structure, while plastics are covalent bonds. The bond strengths in a crystal structure are greater than those of the covalently bonded plastic.
How this translates into super smooth vs. coarse edges is a bit farther than I am willing to guess. But electrons by themselves, it ain't.
Because electrons alone are not what is holding the material together. You are actually dealing with molecular bonds between atoms. So you need to look at bond strengths. Metal cuts plastic because the metal is a crystal structure, while plastics are covalent bonds. The bond strengths in a crystal structure are greater than those of the covalently bonded plastic.
How this translates into super smooth vs. coarse edges is a bit farther than I am willing to guess. But electrons by themselves, it ain't.
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The answer , two knives/blades , one polished one toothy , the end.
1234,,,,
Good answer
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In my class we were told by the teacher that things never physically touch IE: finger on paper because the electrons would repel each other and have an atom sized gap between them. Thats where I got my theory/thought. Is this correct, if so why wouldn't it apply to knives
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agreed.
Same charges repel, that's the underlying principle indeed.
But it's not that simple when you have pure physical interaction between two seperate objects that are strutrally stable.
If electron repulsion alone is enough to break open objects then we probably don't even need knives, we could just use the electrons of our body to "repel" and break open a bank safe or cut open a vehivle to avoid collision...
If you say electrons on the edge repel the material then it sounds like more electrons repel stronger and you have better cutting ability.
Then why do people sharpen their knives so thin when a fat edge leaves you more electrons for repulsion...?
There're variables like Van Der Waal's force and other types of bond(ionic, covalent) that contribute to breaking/establishing intermolecular forces.
Cutting is a pure physical phenomenon that doesn't involved any electron interaction.
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We're gonna get to the bottom of this one
Start with riderV3's post.
Toothed or smooth?
I don't see much potential except people taking side to bash the other side...
:foot::foot:
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The way I see it the electrons are concentrated in a thin V which repels a very thin spot breaking the bonds. Right?
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True enough, the atoms themselves don't touch. But it is still the atoms doing the pushing. The most you can say is that it's the electron cloud that is held together by the atoms. So, you still need to look at the molecular bond strengths (bond strengths between atoms).
Interactions between solids is PhD level stuff. Because to understand the interactions you have to look at molecular orbital energies of electrons. This is far more complex than studying atomic orbital energies. If you really want to pursue this, get a PhD in Physical Chemistry. It's that complex.
But to get back to the smooth vs. coarse question, atomic and molecular distances are so small that fine grind vs. coarse grind doesn't enter into it.