Friction: Force & Electromagnetic Nature

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Friction is not a force applied to a particle but arises from electromagnetic interactions at the atomic level between surfaces. At the macro level, it involves small surface projections colliding, while at the micro level, it relates to the electric fields of protons and neutrons. Friction can occur even with zero or negative normal force, as seen with adhesive tape. Interestingly, adding water can sometimes increase friction, contrary to its usual role as a lubricant. Understanding friction involves examining both macro and micro perspectives of surface interactions.
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What kind of force is Friction, force applied on a particle? Are these are Electromagnetic in nature?
 
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manimaran1605 said:
What kind of force is Friction, force applied on a particle? Are these are Electromagnetic in nature?

Friction doesn't apply to a particle.
But in general, yes, frictional forces ariss from electromagnetic interactions between the atoms at the surface of the two objects.
 
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It really depends upon which "level" you are looking at. From the "macro" level, friction is small projections in the surface hitting and perhaps breaking off against small projections in the object. From the "micro" level, it is the electric fields of the protons and neutrons pressing against one another.
 
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Friction can be quite interesting. The Wikipedia article mentions situations when you can have friction even with zero or negative normal force. It gives adhesive tape as an example. Sometimes adding water (normally considered a lubricant) can also increase friction. For example many people lick their fingers when trying to turn the pages of a newspaper.
 
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