Forces in the context of Virtual work

Electrostatics is a branch of physics that studies slow-moving or stationary electric charges on macroscopic objects where quantum effects can be neglected. Under these circumstances the electric field, electric potential, and the charge density are related without complications from magnetic effects.

Since classical antiquity, it has been known that some materials, such as amber, attract lightweight particles after rubbing. The Greek word ḗlektron (ἤλεκτρον), meaning 'amber', was thus the root of the word electricity. Electrostatic phenomena arise from the forces that electric charges exert on each other. Such forces are described by Coulomb's law.

A mechanical linkage is an assembly of systems connected so as to manage forces and movement. The movement of a body, or link, is studied using geometry so the link is considered to be rigid. The connections between links are modeled as providing ideal movement, pure rotation or sliding for example, and are called joints. A linkage modeled as a network of rigid links and ideal joints is called a kinematic chain.

Linkages may be constructed from open chains, closed chains, or a combination of open and closed chains. Each link in a chain is connected by a joint to one or more other links. Thus, a kinematic chain can be modeled as a graph in which the links are paths and the joints are vertices, which is called a linkage graph.

Dispersive adhesion, also called adsorptive adhesion, is a mechanism for adhesion which attributes attractive forces between two materials to intermolecular interactions between molecules of each material. This mechanism is widely viewed as the most important of the five mechanisms of adhesion due to its presence in every type of adhesive system and its relative strength.

A force gauge (also called a force meter) is a measuring instrument used to measure forces. Applications exist in research and development, laboratory, quality, production and field environment. There are two kinds of force gauges today: mechanical and digital force gauges. Force Gauges usually measure pressure in stress increments and other dependent human factors.