Version 1.0, August 31, 2001, Copyright, Hugh Jack 1993-2001
· Sometimes we are faced with moments that are in awkward positions, We can move these by replacing them with forces and moments in new positions. (Force couples also allow us to rotate the effects of moments)
· Keep in mind that couples cause rotation only, without any translation.
· Consider the basic force couple,
· A force couple acts about an axis. In the previous example the axis was out of the page. The axis can be moved to any position on the rigid body, as long as the direction is maintained. This axis of the couple will be perpendicular to the plane of the forces.
· A sample problem is given using a rope pulling a wedge ([Hibbeler, 1992], prob 4-81, pg. )
· Consider the stress element that was seen earlier in the stress section
