The $4\mathrm{.}1-$kN force $F$ is applied at point $A.$

$($a$)$ Compute the moment of $F$ about point $O,$ expressing it both as a scalar $($positive if $CCW,$ negative if $CW)$ and as a vector quantity.

$($b$)$ Determine the coordinates of the points on the $x-$ and $y-$axes about which the moment of $F$ is zero.

Assume $x_A=0\mathrm{.}9m,y_A=1\mathrm{.}6m,a=6,b=12.$

Answers:

$($a$)$ Scalar:

$M_O=$

$kN*m$

Vector:

$M_0=1i+$ k$)kN*$

$($b$)$ On the $x$ axis:

On the $y$ axis: $$ m