Compute the conductivity of a conductor with a length of 2.0 cm and a cross-sectional area of 0.060 cm2, whose conductance is 3.5 x 103 ohms. σ = ohm-1cm-1 A: 1.2 x 10 5 B: 2.9 x 10 -4 C: 1.1 x 10 2 D: 1.9 x 10 6

A

Explanation:

You are given the following parameters:

Length L = 2.0 cm and

cross-sectional area A = 0.060 cm^2

Conductance = 3.5×10^3 ohms

Conductance is a reciprocal of resistance R

Conductance = (σ × A)/L

Where σ = conductivity

Substitutes all the parameters into the formula

3.5×10^3 = (0.06 × σ)/2

Cross multiply

7×10^3 = 0.06σ

Make σ the subject of formula

σ = 7000/0.06

σ = 116666.67 ohm-1cm-1

σ = 1.2 ×10^5 ohm-1cm-1 approximately

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