Friction coefficient and forces

In summary, the conversation discusses the concept of "mu" in friction and how it relates to the force of friction and the force normal. The coefficient of friction, represented by "mu," is a constant that shows the ratio between these two forces. It can be used to calculate the frictional force on an object. The conversation also mentions helpful resources, such as Wikipedia and a pulley experiment, for further understanding.
  • #1
rkslperez04
31
0
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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  • #2
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
 
  • #3
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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  • #4
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!
 

Related to Friction coefficient and forces

What is the definition of friction coefficient?

The friction coefficient is a dimensionless quantity that represents the amount of friction between two surfaces in contact. It is typically denoted by the Greek letter mu (μ) and is calculated by dividing the force of friction by the normal force between the surfaces.

How does friction coefficient affect the force of friction?

The friction coefficient directly affects the force of friction. A higher friction coefficient means there is more resistance between the surfaces, resulting in a greater force of friction. Similarly, a lower friction coefficient means there is less resistance and a lower force of friction.

What factors influence the friction coefficient?

The friction coefficient is influenced by several factors, including the type of surfaces in contact, the roughness of the surfaces, and the force pressing the surfaces together. Additionally, the presence of lubricants or contaminants can affect the friction coefficient.

How is the friction coefficient measured?

The friction coefficient can be measured experimentally by using a device called a tribometer. This instrument measures the force of friction as two surfaces are rubbed against each other at different speeds and pressures. The resulting data can be used to calculate the friction coefficient.

How can friction coefficient be reduced?

Friction coefficient can be reduced by using lubricants, such as oil or grease, between the surfaces in contact. These substances create a layer between the surfaces, reducing the amount of direct contact and therefore decreasing the friction coefficient. Additionally, using smoother or more polished surfaces can also reduce the friction coefficient.

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