Ohm's law only applies to linear components, of which exactly 0 exist in nature. Everything approximates linearity to varying degrees – resistors approximate i

Ohm's law only applies to linear components, of which exactly 0 exist in nature. Everything approximates linearity to varying degrees – resistors approximate it over a wide range of currents (up until they melt); MOSFETs approximate it until they reach saturation; diodes approximate it only infinitesmally.