# Formula Solid Sphere (E-field Inside) Electric charge    Radius

## Electric field

Unit
Radial outwards directed electric field at the field point $$r$$ within a homogeneously electrically charged sphere.

## Electric charge

Unit
It is the amount of charge that is homogeneously distributed within the entire sphere.

## Field point

Unit
Field point points from the center of the sphere to any point inside the sphere where the electric field $$E(r)$$ is present.

The vacuum permittivity is a physical constant that appears in equations involving electromagnetic fields. It has the following experimentally determined value:$$\varepsilon_0 ~\approx~ 8.854 \, 187 \, 8128 ~\cdot~ 10^{-12} \, \frac{\mathrm{As}}{\mathrm{Vm}}$$