ABSTRACT
This chapter explains the term 'resistance' and describes state the SI unit of measurement of resistance. Resistance is the natural opposition offered by any material to an electric current. The resistance of a material is directly proportional to its length. In other words, doubling the length of a conductor will double its resistance, while halving its length will halve its resistance. The resistance of a material is also inversely proportional to its cross-sectional area. In other words, doubling its cross-sectional area will halve its resistance, while halving its cross-sectional area will double its resistance. Resistance will vary with temperature because, as we have learned, a material's resistivity is affected by temperature. Resistance is directly proportional to the length of a material and inversely proportional to its cross-sectional area. The SI unit of measurement of resistance is the ohm, named in honour of Georg Simon Ohm.
