Grade 12 Physics, Coefficient of Friction

AI Thread Summary
The discussion focuses on deriving the equation for the coefficient of kinetic friction without specific values or mass. Participants clarify that the derivation does not require numerical inputs, emphasizing the importance of understanding the free body diagram. There is confusion about the nature of the object in question, whether it is stationary or moving, which impacts the approach to the derivation. The equation for frictional force and normal force is referenced, indicating foundational concepts in physics. Overall, the conversation aims to clarify the derivation process while addressing uncertainties in the problem statement.
JamesNam
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Homework Statement


Derivation of an equation for the coefficient of kinetic friction
*Since it's just a derivation, values won't be required, right?
*No mass was given

Homework Equations


Ff = μFN
FN = FgCosθ
Fnet= Fapp - Ff - FgSinθ <- Not sure about this.


The Attempt at a Solution


We had to draw a free body diagram so I"ll upload it
 

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Welcome to PF!

Good morning JamesNam! Welcome to PF! :smile:
JamesNam said:

Homework Statement


Derivation of an equation for the coefficient of kinetic friction
*Since it's just a derivation, values won't be required, right?
*No mass was given

Homework Equations


Ff = μFN
FN = FgCosθ


The Attempt at a Solution


We had to draw a free body diagram so I"ll upload it

I'm confused … what exactly is the question? :confused:

(and what's your answer?)
 
Thanks for the welcome! And we have to derive an equation for μk from the free body diagram that I have attatched.
 
is it stationary or moving? :confused:

anyway, show us what you've tried :smile:
 
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