Given that $a=5\mathrm{.}5m,b=3\mathrm{.}5m,c=6\mathrm{.}5m,d=1\mathrm{.}6m,e=12\mathrm{.}0m$ and $=39.$ The force

$F=143N$ is along the direction of CD$.$ Determine the moment of the force $F$ about

the door hinge at $A$ by using $r_{AD}$ and $r_{AC}.$ Note that A and $B$ are hinges and their

exact locations are shown by black dots, they are in $xy$ plane.

Find moment $M_A$ using $r_{AC}$

$M_A$:$1,i+,j+,k$

Find moment $M_A$ using $r_{AD}$

$M_A$

$i+$

i$+$

k$)N*m$