Current Density
### Formula
$$J=\frac{I}{A}$$
### Alternative Form
$$J=nev_d$$
### Terminologies
- J β Current density.
- I β Current.
- A β Cross-sectional area.
- n β Number density.
- e β Electron charge.
- vd β Drift velocity.
### SI Unit
$$Am^{-2}$$
### Usage
- Used to describe current distribution.