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Homework Statement
The turnbuckle is tightened until the tension in cable AB is 1.5 kN. Calculate the magnitude of the moment about point O of the force acting on point A.
Homework Equations
ƩM_{O} = sqrt(M_{x}^{2} + M_{y}^{2} + M^{2})
The Attempt at a Solution
First I identified the coordinates of points A and B:
A = (1.6, 0, 2.4)
B = (2.3, 1.4, 0)
OA = r = <1.6, 1.4, 0>
AB = <0.7, 1.4, 2.4>
AB = 2.865
λ_{AB} = AB/AB
λ_{AB} = 0,2443i + 0.4877j  0.8377k
Then I took the dot product with the tension in the cable AB and the unit vector of AB
T_{AB}.λ_{AB} = 0.36645i + 0.73305J  1.25655K
ƩM_{O} = rXT_{AB}
(01.75932)i (2.81796)J + (1.17288)k
ƩM_{O} = 3.523
But it says my answer is wrong and I don't know where I'm going wrong.
Suggestions would be appreciated
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