Transcription: The topic of this lesson is specific resistance. For a cylindrical conductor such as wire, the resistance is directly proportional to the length of the conductor and inversely proportional to the cross-sectional area. The expression for this relationship is R equals rho times L divided by A, where rho is the constant of proportionality and is called resistivity or specific resistance. Thus, a conductor of a certain material with a length of one meter and having a cross-sectional area of one meter squared will have a resistance of R ohms. Specific resistance is also expressed as the resistance ...
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