Moment vector expression to magnitude of moment

[kleeds]

Homework Statement

find the magnitude and angle of the moment

moment=-2.8i-1.53j+2.24k

force tension=2.4 kN

Homework Equations

rxf=rfsin(theta)

The Attempt at a Solution

i used the cross product to get i j and k
tried sin and cos of vectors but didnt work.
inverse tan of vectors won't give close to correct angles

 

[cepheid]

Welcome to PF!

As far I as I can tell, the first part of the question is simply asking what the magnitude of the given vector is. You have all three components of the vector.

What is the expression for the magnitude of a vector in terms of its components?

 

[kleeds]

I have no idea. The last time i did vectors at least six months ago.

 

[kleeds]

nevermind you square them all, add them, then take the square root.

 

[cepheid]

nevermind you square them all, add them, then take the square root.

Yeah.