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Homework Statement
Shafts A and B connect the gear box to the wheel assemblies
of a tractor, and shaft C connects it to the engine. Shafts A and
B lie in the vertical yz plane, while shaft C is directed along
the x axis. Replace the couples applied to the shafts with a
single equivalent couple, specifying its magnitude and the
direction of its axis.
The Attempt at a Solution
We have to resolve each moment into its components Mx, My, Mz
I am having trouble determining the signs of each... How is this exactly done?
I have:
Ma = (1600 Nm)(sin 20) j + (1600 N m)(cos 20) k
Mb = (1200 Nm)(sin 20) j + (1200 N m)(cos 20) k
I'm being told that the y component of Ma has a NEGATIVE SIGN... Why?
Thanks in advance
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