| electrodynamic force | London Van der Waals forces: See: DLVO theory. (18 Nov 1997) |
|---|---|
| electromagnetic force | <physics> One of the fundamental forces of interaction which influences charged entities. In quantum field theory, the electromagnetic force is mediated by particles of exchange called (virtual) photons. Photons are massless and travel at the speed of light c. The electromagnetic force obeys an inverse square law, which makes sense because it is mediated by particles that have an infinite lifetime (special-relativistically, time stops in a frame moving at c when observed from a non-moving frame). (05 Jan 1998) |
| electromotive force | The force (measured in volts) that causes the flow of electricity from one point to another. (05 Mar 2000) |
| electrostatic force | <radiobiology> Like charges in close proximity produce forces of repulsion between them. Consequently if two surfaces bear appreciable and approximately equal densities of charged groups on their surfaces appreciable forces of repulsion may occur between them. The range of these forces is determined in the main by the ionic strength of the intervening medium, forces being of minimal range at high ionic strength. The forces are effective over approximately twice the double layer thickness. See: DLVO theory. (18 Nov 1997) |
| unit of force | CGS system: dyne, FPS system: poundal, MKS system: newton,SI: newton. (05 Mar 2000) |
| force | <physics> Rate of change of momentum with time. Forces are said to cause accelerations via f = ma (Newton's law). There are four primary forces known presently: the gravitational, electromagnetic, weak nuclear, and strong nuclear forces. The gravitational and electromagnetic forces are long-range (dropping as 1/distance^2), while the nuclear forces are short range (effective only within nuclei, distances on the order of 10^-15 metres). The electromagnetic force is much stronger than the gravitational force, but is generally cancelled over large distances because of the balance of positive and negative charges. See: momentum. (04 Apr 1998) |
| force of infection | <epidemiology> The per capita rate at which susceptibles are infected. (05 Dec 1998) |
| force of mastication | The motive force created by the dynamic action of the muscles during the physiologic act of mastication. Synonym: biting strength, masticatory force. (05 Mar 2000) |
| force platform | A device used to measure the strength, symmetry, and latency of compensatory postural movements when visual, vestibular, and somatosensory stimuli are varied. (05 Mar 2000) |
| force pump | <machinery> A pump having a solid piston, or plunger, for drawing and forcing a liquid, as water, through the valves; in distinction from a pump having a bucket, or valved piston. A pump adapted for delivering water at a considerable height above the pump, or under a considerable pressure; in distinction from one which lifts the water only to the top of the pump or delivers it through a spout. Source: Websters Dictionary (01 Mar 1998) |
| force-velocity curve | The relationship between isotonic velocity of shortening and afterload for a contracting muscle. (05 Mar 2000) |
| lorentz force | <physics> Total electromagnetic force on a charged particle moving in electric & magnetic fields. F = q(E + (v/c)xB). See: force, cross product, charge, velocity, and relevant variable symbols. (09 Oct 1997) |