Ohm's law (옴의 법칙) and conductivity (전기전도도)

ohms_law.png

σ : conductivity

Resistivity (비저항) and resistance (저항)

resistivity.png

: resistivity

resistor.png
resistance.png

Resistor

Mobility (이동도)

mobility.png

μ : mobility

What is the conductivity of a material with charge density ρ and mobility μ?