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प्रश्न
Write the formula of resistivity
उत्तर
Resistance R of a conductor depends on the length ‘l’ and area of cross section ‘A’ of the conductor
`R alpha l`
and `R alpha l/A`
`:. R alpha l/A`
`:. R = rho 1/A` ...(ρ is constant)
where ρ is called resistivity of the conductor.
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