Calculate the conductivity σ of the material of which this wire is made

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To calculate the conductivity σ of the wire, the resistance R can be determined using the formula R = V/I, where V is the potential difference (2.1 V) and I is the current (5.4 A), resulting in R = 0.3889 ohms. The resistivity ρ can be calculated using the formula ρ = R(A/L), where A is the cross-sectional area (1.1 mm² or 1.1 x 10^-6 m²) and L is the length (1.0 m). Substituting the values gives ρ = 0.3889 ohms * (1.1 x 10^-6 m² / 1.0 m), resulting in a resistivity of approximately 4.28 x 10^-7 ohm-m. The conductivity σ is then found using the relationship σ = 1/ρ, leading to a conductivity of about 2.34 x 10^6 S/m. This calculation highlights the relationship between resistance, resistivity, and conductivity in electrical materials.
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A wire is 1.0 m long and 1.1 mm2 in cross-sectional area. It carries a current of 5.4 A when a 2.1 V potential difference is applied between its ends. Calculate the conductivity σ of the material of which this wire is made.

Known data: I hate Wileyplus.

Ok, REAL known data: I know that I have to use 2pi(r), and pi(r)^2

R= (roe)(L)/(A)


I understand that if I were to use a specific material, I could find the resistance. However, this does not ask for that. Please help!
 
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Welcome to PF.

You know the resistance from V/I.

You know the A.

You know the Length.

So what is σ?

σ = 1/ρ
and
R = ρL/A
 
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