virtual : Idioms & Phrases

(Mech.), the law that when several forces are in equilibrium, the algebraic sum of their virtual moments is equal to zero.

(Opt.), the point from which rays, having been rendered divergent by reflection of refraction, appear to issue; the point at which converging rays would meet if not reflected or refracted before they reach it.

noun (computer science) memory created by using the hard disk to simulate additional random-access memory; the addressable storage space available to the user of a computer system in which virtual addresses are mapped into real addresses
virtual memory.

(of a force) (Mech.), the product of the intensity of the force multiplied by the virtual velocity of its point of application; sometimes called virtual work.

noun a hypothetical three-dimensional visual world created by a computer; user wears special goggles and fiber optic gloves etc., and can enter and move about in this world and interact with objects as if inside it

noun (computer science) memory created by using the hard disk to simulate additional random-access memory; the addressable storage space available to the user of a computer system in which virtual addresses are mapped into real addresses
virtual memory.

(Mech.), a minute hypothetical displacement, assumed in analysis to facilitate the investigation of statical problems. With respect to any given force of a number of forces holding a material system in equilibrium, it is the projection, upon the direction of the force, of a line joining its point of application with a new position of that point indefinitely near to the first, to which the point is conceived to have been moved, without disturbing the equilibrium of the system, or the connections of its parts with each other. Strictly speaking, it is not a velocity but a length.