# Formula: Drude Model Electric Current Density    Electric field (E field)    Mean free time    Electron density

## Current Density

Unit
Electric current density represents the current passing through a cross-sectional area.

## Electric field (E field)

Unit
Applied external electric field causing a current density $$j$$. As the E-field increases, the current density also increases.

## Mean free time

Unit
Mean free time is the time that elapses between two collisions. During this time, the electron is accelerated collision-free by the electric field to the drift velocity.

## Electron density

Unit
Electron density specifies the number of electrons per volume.

## Mass

Unit
Mass of the electron. The rest mass of the electron is: $$m ~\approx~ 9.109 \,\cdot\, 10^{-31} \, \mathrm{kg}$$.

## Elementary charge

Unit
The elementary charge is a physical constant and is the smallest, freely existing electric charge in our universe. It has the exact value: $$e ~=~ 1.602 \, 176 \, 634 ~\cdot~ 10^{-19} \, \mathrm{C}$$

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