- Ability to resolve forces into components
- M = Fd
The Attempt at a Solution
Resolve the force acting at an angle into components...
10kN force = -10cos50i - 10 sin 50 j kN
Therefore, resultant R becomes...
= (-10cos50)i + (15 - 3 - 10 sin 50)j kN
= -6.428i + 4.3396j kN
(with a magnitude of 7.756kN)
(b) This is where I get stuck.
I basically calculated the moments created by the individual elements of R,
F1 = 15kn force
F2 = 3kn force
F3 = vertical component 10kn force
and, because I am using the joint with the wall as an origin, the line of action of the horizontal component passes through my origin thus no moment.
M1 = 15*3 = 45kNm
M2 = -3*1.5 = -4.5kNm
M3 = (-10 sin 50)*9 = -68.944kNm
Sum of moments = 45 - 4.5 - 68.944 = -28.444kNm
and then I get stuck. Do you add the moment you've just found to the moment provide in the couple, then sub. back into M=Fd where F=R?
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