On a nanometer scale - a billionth of a meter - friction can cause quite a commotion in tiny devices consisting of only a small number of atoms or particles. Due to their high surface-to-volume ratio, nanomaterials are particularly sensitive to frictional forces
In order to understand the phenomenon of friction on a nanometer scale, a team of engineers from the University of Wisconsin had to think big. Friction is a force acting in any system where moving parts come into contact with each other; The larger the contact area, the greater the force. On a nanometer scale - a billionth of a meter - friction can cause quite a commotion in tiny devices consisting of only a small number of atoms or particles. Due to their high surface-to-volume ratio, nanomaterials are particularly sensitive to frictional forces.
However, researchers have difficulty describing friction in such small dimensions because existing theories are not reliable enough for the practical activity of nanomaterials. Using computer simulations, the research group showed that friction at the atomic level behaves similarly to friction between large objects. Five hundred years after Leonardo da Vinci discovered the basic laws of friction for large objects, the research team has shown that very similar laws also operate at the nanometer level. The team, led by Izabela Szlufarska, professor of materials science and engineering, published its findings in the February issue of the scientific journal Nature.
Current theories about nanoscale friction are based on the idea that nanoscale surfaces are smooth, however, in reality, the surfaces are more like a mountain range, where each peak corresponds to a single atom or atom.
The research team performed computer simulations that treated nanomaterials as a collection of atoms, while tracking their location and interactions throughout the sliding process. "For the first time, we simulated friction in dimensions very similar to experimental conditions while preserving the atomic separation and the practical interactions between them," explains the researcher.
The team discovered fundamental laws of nanoscale friction. They discovered that the friction is proportional to the number of reacting atoms between two nanometer surfaces. The researchers' simulations showed that, at the nanometer level, materials that come into contact with each other behave more like large rough objects rubbing against each other than two perfectly smooth surfaces, as previously thought. "When you look at it closer, the surface is made up of atoms, so the contact is actually rough," explains the researcher.
The information gathered from the researchers' simulations largely matches the experimental information accumulated in the past - something that previous models failed to do. The researchers hope to use the simulations as a tool to understand the mechanisms that affect friction, both at the microscopic and macroscopic levels.
"Today, no one is able to give a reliable forecast regarding expected friction or to design materials with desired friction properties - we have measured a large number of friction coefficients for different materials, but it is not really clear how to attribute them to the properties of the materials," she explains. The origin of friction is truly an open and growing field of research."
The original news from the university
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fresh:
Your questions are based on a basic mixing of concepts between electric charge and electric voltage.
Why do you ask where particles get their electric charge and you don't ask where they get their mass?
Know that the questions are very similar. They are not meaningless, but you still have to learn a lot (a lot!) to start thinking about them seriously.
but what? Note that I said that you must study to think about them seriously - I did not say that studies will give you the answer and that is because the answer is not yet known.
You will be able to learn how the electron's charge is obtained from the charge of the quarks that make it up, but then you will ask - and rightly so - where do these get their charge from.
String theory tries to answer these questions.
A. Ben Ner. Good Morning.
The court will also claim his innocence. And the lock doesn't really lock it because nothing touches there inside the lock or the bars.
The beat had an electrifying contact due to the electrical repulsion in his neutrons I got a static current and there was a pleasant friction
learned gentlemen.
If your words are indeed true that "real contact" does not exist, and the words are indeed acceptable in my opinion, then this has a far-reaching legal significance. For example, the former president, Katsav, will be able to claim that he "didn't really touch" the "conspiracies" as he says and therefore, will claim his legal innocence, at least from the charge of touching.
Regardless of whether it is a fundamental concept or not, the question is where does the charge come from? After all, the electricity has to come from some source (reading/battery for example), an axiom is a mathematical concept, not a physical one.
Hi Ranan,
According to our understanding now (if we ignore for a moment the union between the three strong forces..), the electric force is a basic concept.
But where does the electricity/electrical charge (either negative or positive) found in electrons/neutrons come from?
fresh:
You want to tell us that you really don't know that the electric attraction and repulsion forces are forces that act between electric charges and not between batteries?
The protons and electrons are electrically charged.
The electrons are negatively charged and the protons are positively charged.
Since the electrons are on the outer part of the atom, the encounter between two atoms usually brings their electrons together and hence the repulsion that point talked about (two charges of the same sign repel each other)
To the point: How do electric forces repel? Where does the electricity come from? There was no such simulation in Teriya.
Indeed, what is real contact between two objects?
To a point:
The electric attractive forces between the particles must also be added (in addition to the repulsive forces you mentioned).
The stupid and speculative movie "Blip" actually educated the masses because nothing touches anything.
Just to mention, as everyone knows, that "contact" refers to electrical forces that repel one atom from another. There is nothing that touches anything else, as little children are wont to think.