A flywheel must be held from rotating about shaft A while a nut on it is tightened as shown $($in Figures below$).($a$)$ Which position should the wrench be in to have minimum moment about A$?($b$)$ Calculate the moment in each case.

A$.($a$)$ case $($i$)$

$($b$)($i$)M=-140N0\mathrm{.}15m=21N*m,$ Clockwise and $($ii$)M=-140N0\mathrm{.}65m=91N*m,$ Clockwise

B$.($a$)$ case $($ii$)$

$($b$)($i$)M=-140N0\mathrm{.}15m=21N*m,$ Clockwise and $($ii$)M=-140N0\mathrm{.}65m=91N*m,$ Clockwise

C$.($a$)$ case $($ii$)$

$($b$)($i$)M=140N0\mathrm{.}25m=21N*m,$ Clockwise and $($ii$)M=-140N0\mathrm{.}65m=91N*m,$ Clockwise

D$.($a$)$ case $($i$)$

$($b$)($i$)M=-140N0\mathrm{.}35m=49N*m,$ Anticlockwise and $($ii$)M=-140N0\mathrm{.}25m=35N*m,$ Anticlockwise

E$.($a$)$ case $($ii$)$

$($b$)($i$)M=140N0\mathrm{.}15m=21N*m,$ Anticlockwise and $($ii$)$

$M=140N0\mathrm{.}65m=91N*m,$ Anticlockwise