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# 5.4.10: Bubble Inside a Uniform Solid Sphere

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$$\text{FIGURE V.11}$$

$$\text{P}$$ is a point inside the bubble. The field at $$\text{P}$$ is equal to the field due to the entire sphere minus the field due to the missing mass of the bubble. That is, it is

$\textbf{g} = -\frac{4}{3} \pi G ρ \textbf{r}_1 - (-\frac{4}{3} \pi G ρ \textbf{r}_2) = -\frac{4}{3} \pi G ρ ( \textbf{r}_1 - \textbf{r}_2) = -\frac{4}{3} \pi G ρ \textbf{c}. \label{5.4.26} \tag{5.4.26}$

That is, the field at $$\text{P}$$ is uniform (i.e. is independent of the position of $$\text{P}$$) and is parallel to the line joining the centres of the two spheres.

This page titled 5.4.10: Bubble Inside a Uniform Solid Sphere 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.