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Homework Statement
The turnbuckle is tightened until the tension in the cable AB equals 2.9 kN. Determine the vector expression for the tension T as a force acting on member AD. Also find the magnitude of the projection of T along the line AC.
Homework Equations
The Attempt at a Solution
I was able to find the vector expression for T without any real trouble:
AB = <2.6, 1.7, 6.1>
AB = sqrt(2.6^{2}+ 1.7^{2} + (6.1)^{2})
T*AB/AB = 0.42364<2.6, 1.7, 6.1>
T = 1.101i + 0.7201j  2.584k
I know this part is correct but I'm having difficulty doing the projection.
I tried taking taking the dot product of the T vector with the unit vector AC:
AC = ,2.6, 2.8, 6.1>
AC = sqrt(2.6^{2} + (2.8)^{2} + (6.1)^{2})
AC = 7.1979
AC/AC = 0.3612, 0.389, 0.8475
T°AC/AC = 1.101*0.3612 +(0.389*0.7201)+(0.8475*2.584)
= 2.2746
But it says my answer is wrong and I'm not sure where I'm going wrong.
Advice would be greatly appreciated.
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