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# 5.8.4: Infinite Plane Lamina

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The field above an infinite uniform plane lamina of surface density $$σ$$ is $$−2 \pi Gσ$$. Let $$\text{A}$$ be a point at a distance a from the lamina and $$\text{B}$$ be a point at a distance $$b$$ from the lamina (with $$b > a$$), the potential difference between $$\text{B}$$ and $$\text{A}$$ is

$ψ_{\text{B}} - ψ_{\text{A}} = 2 \pi G σ (b-a). \label{5.8.14} \tag{5.8.14}$

If we elect to call the potential zero at the surface of the lamina, then, at a distance $$h$$ from the lamina, the potential will be $$+2 \pi Gσh$$.

This page titled 5.8.4: Infinite Plane Lamina is shared under a CC BY-NC 4.0 license and was authored, remixed, and/or curated by Jeremy Tatum via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.