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Current

A negligibly ...

Question

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

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Solution

Let resistivity coefficient be $ρ$
$R = ρ \frac{l}{A}$
$ρ = \frac{R A}{l}$
$ρ = 2 \times 10^{- 7} Ω m$

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