Does friction in any way increase when the surfaces get very smooth

AI Thread Summary
Friction can increase when surfaces are very smooth due to the phenomenon of cold welding, where smooth surfaces adhere strongly in a vacuum. This adhesion is primarily attributed to van der Waals forces, which are a result of electromagnetic interactions at a microscopic level. The discussion clarifies that van der Waals forces fall under the umbrella of electromagnetism. Understanding these forces is essential for grasping the relationship between surface smoothness and friction. The connection between surface characteristics and friction is complex and influenced by various physical principles.
arun babu
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does friction in any way increase when the surfaces get very smooth ...?

a teacher told us that it can increase due to electromagnetism...is it true...i searched the net but couldn't get any useful info...
 
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arildno said:
Look up on the subject of cold welding.
http://en.wikipedia.org/wiki/Cold_welding

thanks arildno...i viewed the above linked and learned that when very smooth surfaces are brought together in vacuum they adhere very strongly to each other...but it is due to van der waals forces right?k...this may be a silly question...but does van der waals forces come under electromagnetism...
 


Yes, van der Waals-forces ARE electromagnetism written small.
 
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