In this paper are proposed a rule for the determination of the support of the resultant vector of the d'Alembert's fictitious forces for plates having uniform rotation motion and a formula for calculus of the centrifugal moment for plane plates.
--[J.sub.xz] is the centrifugal moment with respect to the Ox and Oz axes;
So, the centrifugal moment is equal with the product between the mass of the plate, the coordinate of center of mass of the rotation body, generated by plate, and the coordinate of center of mass of the plate on the perpendicular axis on the rotation axis.
For example, for the plate from the figure 4, the centrifugal moment can be quickly obtained using the relation (10).
Also, in problems where appear plates and bars having rotation motion, the centrifugal moments are necessary when it is applied the theorem of the angular momentum.
In the technical literature, the values of the centrifugal moments are calculated by the "classical" method, by integration (Teodorescu, 2007; Hibbeler, 2009), or by studying the vibrations of the system (Belyakov & Seiranyan, 2008).