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What are the equations to calculate friction

  • #1
What are the equations that can be used to calculate friction, be detailed i dont know much about.
 

Answers and Replies

  • #2
tiny-tim
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welcome to pf!

hi ellomoto135! welcome to pf! :smile:

there isn't much to say …

if the surfaces aren't moving, and aren't "about to move", the friction force is simply part of the reaction force … you calculate it exactly as if the surfaces were fixed together

if they are moving, you have to look up the kinetic (dynamic) coefficient of friction, µk, in a table (or it'll be given in an exam question), and then
the friction force is µkN (where N is the normal force)

if they are "about to move", you have to look up the static coefficient of friction, µs, in a table (or it'll be given in an exam question), and then
the friction force is µsN (where N is the normal force) :wink:
 
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