'''Electrical resistance''' is a measure of how much a substance impedes the flow of [[electrons]].<ref>http://www.answers.com/topic/electrical-resistance-1</ref> Resistance is represented with the symbol ''R'', and its [[SI]] unit is the [[Ohm]] (Ω). | '''Electrical resistance''' is a measure of how much a substance impedes the flow of [[electrons]].<ref>http://www.answers.com/topic/electrical-resistance-1</ref> Resistance is represented with the symbol ''R'', and its [[SI]] unit is the [[Ohm]] (Ω). |