Answer
$11.2~N\cdot m$, clockwise
Work Step by Step
We can determine the required moment of force as follows:
First of all, we find the x and y components of force
$F_x=50cos60=25N$
and $F_y=50sin60=43.3N$
Now the moment arms in the x and y direction are given as
$d_x=100(10^{-3})+[200(10^{-3})cos 45+100(10^{-3})]=0.3414m$
and $d_y=200(10^{-3})sin 45=0.1414m$
Now, we can find the moment of force
$M_O=F_yd_x+F_xd_y$
We plug in the known values to obtain:
$M_O=43.3N(0.3414m)-25N(0.1414m)=11.2N.m$
