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. :)
 
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