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Homework Statement
Here's a picture of the set up.
I need to find out what angle I need to have the plane raised to so that the blocks aren't moving.
Homework Equations
F = ma
The Attempt at a Solution
For the first block
[tex]F_k=μ_kF_N[/tex]
[tex]F_T+F_Nμ_kF_N+2mgcosθ+2mgsinθ=0[/tex]
Since the [tex]F_N[/tex] and [tex]2mgcosθ[/tex] cancel each other, I eliminated them from the problem. I set the right side equal to 0 since there is no acceleration
Then I get
[tex]F_T = μ_kF_N + 2mgsinθ[/tex]
For the right block [tex]mg = F_T[/tex]
So I input that into my equation for the other block and get
[tex]mg=μ_kF_N+2mgsinθ[/tex]
For [tex]F_N[/tex] I plug in [tex]2mgcosθ[/tex]
And get [tex]mg=μ_k2mgcosθ+2mgsinθ[/tex]
And this is when I know something is wrong. That [tex]μ_k[/tex] is the coefficient for kinetic friction, not static friction, and I have [tex]sinθ[/tex] and [tex]cosθ[/tex], so that's two unknowns.
How do I find out the coefficient for static friction? Do I even need it?
And what went wrong with my analysis of this problem?
Thanks.
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