Resistance
In electricity, the property of an electric circuit or part of a circuit transforms electric energy into heat energy in opposing electric current. Resistance involves collisions of the current-carrying charged particles with fixed particles that make up the structure of the conductors. Resistance is often considered localized in such devices as lamps, heaters, and resistors, in which it predominates. However, it is characteristic of every circuit part, including connecting wires and electric transmission lines. The dissipation of electric energy in the form of heat, even though small, affects the amount of electromotive force, or driving voltage, required to produce a given current through the circuit. The electromotive force V (measured in volts) across a circuit divided by the current I (amperes) through that circuit defines quantitatively the amount of electrical resistance R. Precisely, R = V/I. Thus, if a 12-volt battery steadily drives a two-ampere current through a length of wire, the wire has a resistance of six volts per ampere or six ohms. The ohm is the common unit of electrical resistance, equivalent to one volt per ampere and represented by the capital Greek letter omega, Ω.
The resistance of a wire is directly proportional to its length and inversely proportional to its cross-sectional area. Resistance also depends on the material of the conductor [Online Encyclopedia Britannica].
The degree to which a substance prevents the flow of an electric current through it [Cambridge Online Dictionary].
A property of a conductor by which the current passage is opposed, causing electric energy to be transformed into heat: equal to the voltage across the conductor divided by the current flowing in the conductor: usually measured in ohms [Dictionary.com].
Resistance. Online Encyclopedia Britannica. Retrieved from: https://www.britannica.com/technology/resistance-electronics
Resistance. Cambridge Online Dictionary. Retrieved from: https://dictionary.cambridge.org/dictionary/english/resistance
Resistance. Dictionary.com. Retrieved from: https://www.dictionary.com/browse/resistance