The **drift velocity** is the average velocity that a particle, such as an electron, attains due to an electric field. It can also be referred to as axial drift velocity since particles defined are assumed to be moving along a plane. In general, an electron will 'rattle around' in a conductor at the Fermi velocity randomly. An applied electric field will give this random motion a small net velocity in one direction.

In a semiconductor, the two main carrier scattering mechanisms are ionized impurity scattering and lattice scattering.

Because current is proportional to drift velocity, which is, in turn, proportional to the magnitude of an external electric field, Ohm's law can be explained in terms of drift velocity.

Drift velocity is expressed in the following equations:, where is the current density, is charge density in units C/m3, and *v*_{avg} is the average velocity of the carriers (drift velocity);

- , where μ is the electron mobility in (m^2)/) and
*E*is the electric field in V/m.

Read more about Drift Velocity: Numerical Example

### Other articles related to "drift velocity, velocity, drift":

... At low fields, the

**drift velocity**vd is proportional to the electric field E, so mobility μ is constant ... As the electric field is increased, however, the carrier

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**Drift Velocity**- Numerical Example

... The

**drift velocity**therefore can be calculated By comparison, the Fermi

**velocity**of these electrons (which, at room temperature, can be thought of as their approximate

**velocity**in the ... case of alternating current, the direction of electron

**drift**switches with the frequency of the current ... In the example above, if the current were to alternate with the frequency of F=60 Hz,

**drift velocity**would likewise vary in a sine-wave pattern, and electrons would fluctuate about their initial ...

**Drift Velocity**in An Electric Field

... faster and faster instead it moves with a finite average

**velocity**, called the

**drift velocity**... electrons and holes, will typically have different

**drift**velocities for the same electric field ... In these cases,

**drift velocity**and mobility are not meaningful ...

... The average

**velocity**due to the thermal energy is zero since the electrons are going in every direction, leading to

**velocity**vectors that are randomly oriented ... The electrons are given a

**velocity**away from the (negative source of the) field, which leads to these collisions with the fixed ions ... a release of it), is a small value called

**drift velocity**...

### Famous quotes containing the word drift:

“But now they *drift* on the still water,

Mysterious, beautiful;”

—William Butler Yeats (1865–1939)