Friction coefficient and forces

AI Thread Summary
The discussion clarifies the concept of the friction coefficient, denoted as "mu" (μ), which is a dimensionless constant representing the ratio of the force of friction to the normal force acting on an object. The force of friction can be calculated using the formula F = μmg, where mg is the weight of the object. Participants emphasize that understanding μ is crucial for solving problems related to frictional forces. Resources like Wikipedia and other educational sites are recommended for further clarification. Overall, the conversation highlights the importance of grasping the relationship between the friction coefficient and the forces involved in motion.
rkslperez04
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Hey there,

Can you someone explain the "mu" in friction?

I understand that Force=Mass*Acceleration but then it asks for coeffeiencent of friction??

F=ukFn ?

I see it says that F=mg but the friction equalls the constant of the "mu"...the examples in the book are sketchy and wording is over my head.
 
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U stands for mu_k in this post

u is the friction coefficient. The force of friction is found by multiplying u, which has no units, by mg.

F=umg

Then solve for u. If you know u you can find the force required to move an object across the surface.

F=uma
 
If you want more, there is a decent wikipedia entry on the http://en.wikipedia.org/wiki/Friction_coefficient#Coefficient_of_friction" that you might want to check out.

Basically, the value "mu" is a constant (depending on the surfaces) that shows the ratio of the force of friction and the force normal, which is the same as the force pushing the object into the surface.

Here is another http://www.phy.ntnu.edu.tw/ntnujava/viewtopic.php?t=18" with an explanation you might want to check out. Just play around with the coefficient and you will start to see the relationship between it and F.
 
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GREAT ... the wikipedia was helpful...Im going to apply it to the problems I have...

and..

Thanks for pulley site.. we just an experiment like that in class!

>>>So.. When it says find frictional force..

I just mulipliy u by the force..

Friction="mu" times "force on object"


Im going to the learning lab on campus for extra help... thanks for filling in the gaps!
 
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