resistance, in biology: see immunity.

resistance, in psychiatry: see psychoanalysis.

resistance, property of an electric conductor by which it opposes a flow of electricity and dissipates electrical energy away from the circuit, usually as heat. Optimum resistance is provided by a conductor that is long, small in cross section, and of a material that conducts poorly. Resistance is basically the same for alternating and direct current circuits (see impedance). However, an alternating current of high frequency tends to travel near the surface of a conductor. Since such a current uses less of the available cross section of the conductor than a direct current, it meets with more resistance than a direct current. In circuit analysis an ideal resistor, i.e., a circuit component whose only property is resistance, is called a resistance. The phenomenon of resistance arises from the interactions of electrons with ions in the conductor. The unit of resistance is the ohm. See superconductivity; Ohm's law; conduction.

or passive resistance

Refusal to obey government demands or commands and nonresistance to consequent arrest and punishment. It is used especially as a nonviolent and usually collective means of forcing government concessions and has been a major tactic of nationalist movements in Africa and India, of the U.S. civil rights movement, and of labour and antiwar movements in many countries. Civil disobedience is a symbolic or ritualistic violation of the law, rather than a rejection of the system as a whole. The civil disobedient, finding legitimate avenues of change blocked or nonexistent, sees himself as obligated by a higher, extralegal principle to break some specific law. By submitting to punishment, the civil disobedient hopes to set a moral example that will provoke the majority or the government into effecting meaningful political, social, or economic change. The philosophical roots of civil disobedience lie deep in Western thought. Cicero, Thomas Aquinas, and John Locke, among others, appealed to systems of natural law that take precedence over the laws created by communities or states (positive law). More modern advocates and practitioners of civil disobedience include Henry David Thoreau, Mohandas K. Gandhi, and Martin Luther King, Jr.

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or Underground

Clandestine groups opposed to Nazi rule in German-occupied Europe in World War II. The groups included civilians who worked secretly against the occupation and armed bands of partisans or guerrilla fighters. Resistance activities ranged from assisting the escape of Jews and Allied airmen shot down over enemy territory to committing sabotage, ambushing German patrols, and sending intelligence information to the Allies. Resistance groups were not always unified; in some countries, rival groups divided along communist and noncommunist lines. However, in France the clandestine National Council of the Resistance coordinated all French groups, which gave support to the Normandy Campaign and participated in the August 1944 uprising that helped liberate Paris. Resistance groups in other northern European countries also undertook military actions to help the Allied forces in 1944–45.

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Resistance may refer to:

Physics

• Electrical resistance, a measure of the degree to which an object opposes an electric current through it
• Friction, the force that opposes (relative) motion
• Drag (physics) ("air resistance"), fluid or gas forces opposing motion and flow
• Geological resistance, a measure of how well minerals resist erosive factors
• Hydraulic conductivity, the ease with which water can move through pore spaces or fractures in soil or rock
• Thermal resistance, a measure of difficulty of heat transfer through a substance
• Thermal conductivity, how well heat is conducted through a substance
• Thermal resistance in electronics, heat considerations in electronics design

Biology

• Drug resistance
• Antibiotic resistance, the ability of a microorganism to withstand the effects of antibiotics
• Resistance to antiviral drugs, the ability of a population of viruses to withstand the effects of an antiviral drug.
• Immune system, the system in organisms that provides disease resistance
• Disease resistance in fruit and vegetables
• Pesticide resistance, resistance of insects, weeds, rodents, and other "pests" to improperly used pesticides
• Systemic acquired resistance, a response in plants that occurs following exposure to a pathogen
• Vascular resistance, the resistance to flow that must be overcome in order for blood to circulate through the body.

Politics and Military

• Resistance movement, a group trying to thwart foreign occupation
• Resistance during World War II
• French Resistance
• Resistance (socialist youth organisation), an Australian Marxist organisation
• Draft resistance, organized or personal opposition to military conscription
• HMS Resistance, a British Navy ironclad battleship
• Resistance (military) is the ability of an organized force to stand on the defensive
• White Aryan Resistance

Entertainment

• in music:
• Resistance (Burning Spear album), 1986 album
• Resistance (Mika Nakashima album), 2002 album
• Resistance (Alove for Enemies album), 2006 album
• Resistance, a song by Japanese band High and Mighty Color
• La Resistance a song from the musical South Park: Bigger, Longer & Uncut
• Resistance Records, a white power music label
• Resistance Productions, a record label
• in videogames:
• Resistance: Fall of Man, a Sony PlayStation 3 game
• Resistance 2, sequel to Resistance: Fall of Man
• Resistance: Retribution, a Sony PlayStation Portable game
• Operation Flashpoint: Resistance, expansion pack of video game Operation Flashpoint.
• in television:
• Resistance (V TV series), a group of humans opposing an alien takeover in the V television series
• Resistance (Battlestar Galactica), a Battlestar Galactica episode
• "Resistance" (Star Trek: Voyager episode), the 28th episode of Star Trek: Voyager
• other:
• Resistance (film), a 2003 war movie, with Bill Paxton
• Resistance (novel), a 2007 historical novel by Owen Sheers

Other

• La Résistance (professional wrestling)
• Resistance (technical analysis), a price level in security trading that, if reached, activates many sell triggers
• Resistance welding, a group of welding processes
• Psychological resistance, the act of defending one's position in response to confrontation

See also

• Resilience
• Resistor