In many technical problems, where appear plane plates having rotation motion, the solving of the problem of determination of the reactions is simple if is known the position of the support of resultant vector of d'Alembert's fictitious forces system.
THE SUPPORT OF THE RESULTANT VECTOR OF THE D'ALEMBERT FICTITIOUS FORCES SYSTEM
It follows that the system of d'Alembert's fictitious forces is a parallel forces system and can be replaced by the resultant vector.
Because the plate is entirely situated on the same side of the rotation axis, all the d'Alembert's fictitious forces have the same sign.
If the plane plate has uniform rotation motion ([epsilon] = 0), the resultant vector of the d'Alembert's fictitious forces system will be parallel with the Ox axis.
As spoken of by contemporary physicists, inertial or fictitious forces, though related to Newton's vis inertiae, do not have exactly the same meaning, though for both, a body's inertia is acknowledged as a true source of the phenomena under consideration.
(58) Mach argued that inertial or fictitious forces are caused by the distant matter of the universe and that if the background of fixed stars did not exist, there would be no inertial forces.
"Fictitious forces are distinguished from 'actual' forces by the fact that the fictitious forces depend only on the motion ...
The perception of inflated strength can be reinforced through a mix of real and fictitious forces
or by inventing a completely notional order of battle in a locale an enemy considers critical, to include bogus headquarters and forces, communications networks and radio traffic, supply depots and other logistic elements, water facilities, pipelines, telephone and telegraph lines, and railroads and railheads.
Since such fictitious forces
are always orthogonal to the velocity of a particle in motion, for rotating observers it turns out that the time rate of change of kinetic energy of the particle is equal to zero, as obtained by equation (1).