If F_1 = 100N , F_2 = 120N and F_3 = 80N , determine the magnitude and coordinate direction angles of the resultant couple moment.
M=r x F
MR=Ʃ(r x F)
The Attempt at a Solution
I found the couple moment for each force:
M1=F1d=100(0.2) or (-20j using right hand rule)
M2=F2d=120(0.2) or +24i
M3=F3d=80(0.2) or -16k
M4=this is what im having problems with...not sure how to get the moment for F4... if do 150(.3)(cos30)=38.97 i get the wrong resultant.
The correct answer should be (MC)R=71.9 Nm...
Any help would be greatly appreciated.