Current density via number density and drift velocity

Current density is the amount of charge per unit time that flows through a unit area of a chosen cross section. The current density vector is defined as a vector whose magnitude is the electric current per cross-sectional area at a given point in space, its direction being that of the motion of the positive charges at this point.

Conditions:

1. Charge carriers carry the the same amount of charge.

Links:

1. Wikipedia, first formula with adjustments.

current_density

current_density of charge carriers.

Symbol:

j

Latex:

\(j\)

Dimension:

current/area

number_density

number_density, or number of charge carriers per unit volume.

Symbol:

n

Latex:

\(n\)

Dimension:

1/volume

drift_velocity

drift_velocity of charge carriers.

Symbol:

u

Latex:

\(u\)

Dimension:

velocity

charge

charge of the charge carriers.

Symbol:

q

Latex:

\(q\)

Dimension:

charge

law

j = q * n * u

Latex:

\[j = q n u\]