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प्रश्न
Define the term 'electrical conductivity' of a metallic wire. Write its S.I. unit.
उत्तर
The electrical conductivity of a metallic wire is defined as the ratio of the current density to the electric field it creates.
Electrical conductivity, `σ J/E` S.I. unit = (mho m-1) or (ohm m).-1
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