- #1
Northbysouth
- 249
- 2
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
ƩMO = sqrt(Mx2 + My2 + M2)
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
λAB = AB/|AB|
λAB = 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
TAB.λAB = 0.36645i + 0.73305J - 1.25655K
ƩMO = rXTAB
(0-1.75932)i -(-2.81796)J + (1.17288)k
ƩMO = 3.523
But it says my answer is wrong and I don't know where I'm going wrong.
Suggestions would be appreciated