Capsule (geometry)

A capsule (from Latin , "small box or chest"), or stadium of revolution, is a basic three-dimensional geometric shape consisting of a cylinder with hemispherical ends. Another name for this shape is spherocylinder.

The shape is used for containers for pressurised gasses and for pharmaceutical capsules.

The volume of a capsule is calculated by the formula ${\displaystyle V=\pi r^{2}\left({\frac {4}{3}}r+a\right)}$ where ${\displaystyle r}$ is the radius of the cylinder and hemispheres and ${\displaystyle a}$ is the height of the cylindrical part.

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