Coefficient of Friction Problem

AI Thread Summary
To find the coefficient of kinetic friction for a block accelerating down an inclined plane, start by analyzing the forces acting on the block using a free body diagram. The problem provides the acceleration (3.7 m/s²) and the angle of the incline (26 degrees), but not the mass or gravitational force. By breaking down the gravitational force into its x- and y-components, you can derive the normal force (Fn) without needing the mass. Using the equation Fk = μk * Fn, it is possible to express the coefficient of friction (μk) in terms of the known variables. This approach allows for solving the problem without specific values for mass or gravitational force.
CeceBear
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Homework Statement


A block accelerates at 3.7 m/s^2 down a plane at an angle of 26 degrees. Find the coefficient of kinetic friction between the block and the inclined plane. The acceleration of gravity is 9.81 m/s^2.*


Homework Equations


\SigmaF = ma
F_{}k = \mu_{}k * F_{}n


The Attempt at a Solution


I've drawn the free body diagram and I am currently stuck. The problem doesn't give any values for any of the forces and I'm not sure how to calculate ANY of the forces with just acceleration and an angle.

*This is the complete problem, but on my worksheet it comes with an image diagram.
 
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Start off by finding the x-, y-components of Fg. Then you'll be able to solve for Fn.
 
qswdefrg said:
Start off by finding the x-, y-components of Fg. Then you'll be able to solve for Fn.

I only have the angle measure though. The problem doesn't give the value for Fg. And it doesn't tell me mass either so I can't even do Fg = mg.
 
CeceBear said:
I only have the angle measure though. The problem doesn't give the value for Fg. And it doesn't tell me mass either so I can't even do Fg = mg.

Just do it with the variables. You'll find that you don't need to know the mass to solve for mew. :)
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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