Drift Velocity And Resistance
Drift velocity and resistance cheat sheet

Drift velocity:

The average velocity of charge carriers under an applied electric field.

SI unit: meters per second (m/s)

Mobility:

The drift velocity per unit electric field strength

SI unit: square meter per voltsecond (m2/Vs)

Resistivity:

Resistance of a conductor of unit length and unit crosssectional area.

SI unit: ohmmeter (Ωm)

Ohm’s law:

The current through a conductor is directly proportional to the voltage across it and inversely proportional to its resistance.

SI units:
 Current: Ampere (A)
 Voltage: Volt (V)
 Resistance: Ohm (Ω)

Temperature dependence of resistivity:

Metals: resistivity increases with temperature.

Semiconductors: resistivity decreases with temperature.

Superconductivity:

Zero electrical resistance at a characteristic temperature (critical temperature).

Requires cooling below the critical temperature.