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Homework Statement
Two objects are connected by a light string that passes over a frictionless pulley as shown in the figure below. m1 = 8.32 kg, m2 = 6.40 kg, and = 56°. When released from rest, m1 accelerates downward at 2.210 m/s2. For this to happen, the coefficient of kinetic friction must be [blank], and to even begin sliding in the first place the coefficient of static friction must be [greater than or less than] than [blank] .
link to figure http://www.webassign.net/userimages/SerPSE8-5-p-030-phi.png?db=v4net&id=208569
Homework Equations
F=ma
Fk=μN
The Attempt at a Solution
Ok here goes. I 'solved' this with great confidence, only getting wrong answers. Hopefully you guys can pinpoint where I went wrong.
So I started with drawing my FBD's and what not, and I want to find the Tension in the string first. I set this up by using m1, since it's hanging and should be fairly straightforward.
mg-T = ma
(8.32)(9.8)-T = (8.32)(2.21)
I got T = 63.1488N
After having that I figured I would use m2's forces in the x direction to solve for μ. I set up the equation by the following:
Fxnet = Tcos34-mgsin34-μmgcos34 = ma, and here I used acos34 since that would be the acceleration in the x direction. I solved and got μ = .1068 but that is the wrong answer. I am very confused.
Thank you in advance for all help!