What is the Moment Produced by a Perpendicular Force on an Inclined Plane?

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Homework Statement



hibb4-48.gif


Force F acts perpendicular to the inclined plane ABC. Assume x0 = 2.32 m, y0 = 3.44 m, z0 = 2.94 m, and F = 459 N.
Determine the moment produced by F about point B; What are the x,y,z component.

Homework Equations



Cross Product

The Attempt at a Solution



A (0,0,2.94)
B (2.32,0,0)
C (0, 3.44,0)

rac = 3.44j -2.94k
rbc = -2.32i + 3.44j
rac x rbc = {10.1136,6.8208, 7.9808}

uf = [rab x rbc]/[magnitude]={0.693785,0.467901,0.547477}
F=459*uf = {318.545, 214.832, 251.112}
mb = rbc * F = {864.44, 582.997, -1593.75}

I am wrong. It has been hours. Any help would be great
 
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What is the definition of a moment vector in terms of the force vector and the radius vector?
 
The Rab and Rbc vectors are right, and so is their cross product, as well as the unit vector in the direction of the force. But I got 318.447i + 214.766j + 251.292k for the force vector. Oddly enough, I got the same moment though. Is the x, y, and z components at the end supposed to be the answer?
 
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Yeah that's what i did but I'm always wrong
 
And yes gildomar, the answer is the components
 
Wow, nevermind. I actually got it right.. I just kept on putting N instead of N*m... I am never taking physics again.

thanks anyway