Question 6

A negligibly small current is passed through a wire of length 15 m and uniform cross-section 6.0 x 10^{-7} m^{2}, and its resistance is measured to be 5.0 Ω. What is the resistivity of the material at the temperature of the experiment?

Answer

Length of the wire, *l* =15 m

Area of cross-section of the wire, *a* = 6.0 × 10 ^{- 7} m^{2}

Resistance of the material of the wire, *R* = 5.0 Ω

Resistivity of the material of the wire = *ÃÂ*

Resistance is related with the resistivity as

Therefore, the resistivity of the material is 2 × 10 ^{- 7} Ω

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- NCERT Chapter

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