If a resistance of 3.5 Ohms was measured using the 4-pin Wenner method with a pin spacing of 2 meters, what is the resistivity?

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If a resistance of 3.5 Ohms was measured using the 4-pin Wenner method with a pin spacing of 2 meters, what is the resistivity?

In a four-pin Wenner array, the apparent resistivity is found with ρ = 2π a R, where a is the spacing between adjacent electrodes and R is the measured resistance between the outer current electrodes. Here, a = 2 m and R = 3.5 Ω, so ρ = 2π × 2 × 3.5 = 14π ≈ 43.98 Ω·m. Converting to ohm-centimeters gives ρ ≈ 4398 Ω·cm (since 1 m = 100 cm). The answer is about 4397–4398 Ω·cm, which aligns with the calculation. Remember to keep a in meters when using ρ in Ω·m, then convert to Ω·cm for the final unit.

In a four-pin Wenner array, the apparent resistivity is found with ρ = 2π a R, where a is the spacing between adjacent electrodes and R is the measured resistance between the outer current electrodes. Here, a = 2 m and R = 3.5 Ω, so ρ = 2π × 2 × 3.5 = 14π ≈ 43.98 Ω·m. Converting to ohm-centimeters gives ρ ≈ 4398 Ω·cm (since 1 m = 100 cm). The answer is about 4397–4398 Ω·cm, which aligns with the calculation. Remember to keep a in meters when using ρ in Ω·m, then convert to Ω·cm for the final unit.

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