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Since we know that atomic particles like electrons and protons repel each other, and since we and the objects that we can hold are all made up of these particles, then how can I, for instance, hold a cup of water in my hand and lift it up? wouldn't the particles in it repel the particles in my hand and prevent me from lifting it? I can understand that I can touch it microscopically and not macroscopically, but then how can I move it microscopically?

Note: by particles repel each other I mean similar particles.

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3 Answers 3

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The Van der Waals force between atoms and molecules can be attractive or repulsive depending on the distance. As for microscopic mechanisms of friction (which let us hold a cup), they are adhesion, deformation, ratchet, cobblestone mechanisms (Mechanisms of Dry Friction, Their Scaling and Linear Properties. (2008). NanoScience and Technology, 27–45. doi:10.1007/978-3-540-78425-8_3)

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  • $\begingroup$ the first answer that addresses the question I am really asking, yes I am talking about the friction at the atomic level and how it happens, I will accept this answer as it points me to the terms that lead to solving my problem, but please can you provide links or more brief info about each term as some of them have meanings in different contexts $\endgroup$ Commented Dec 26, 2021 at 9:58
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    $\begingroup$ @User0123 : I would not like to provide numerous quotes from the above reference. I understand that it may be unavailable to you, but alternatively you can google something like friction microscopic mechanisms . $\endgroup$
    – akhmeteli
    Commented Dec 26, 2021 at 11:05
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The notion, that atomic particles repelled each other is wrong, only particles of the same charge repel each other , your cup is neutral (as many negativ electrons as positiv protons) as your hand is. And you can apply pressure to the cup, to hold and lift it.

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  • $\begingroup$ This doesn't answer the question really, your answer is like answering with another question, I zm asking about things at the atomic level, and you just say I can apply pressure, but how does this explain what's happening to lift the cup (i.e. to create a "muscular force" to lift the cup)? $\endgroup$ Commented Dec 26, 2021 at 8:09
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The cup and your hand do repel each other. Otherwise your hand would just pass through it. But the repulsive force is very short ranged because both your and the cups net charge is zero. Once you get close enough, the outermost electrons in your hand and the cup start to see each other and repel.

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