Ohm's Law

An empirical relation that, in its simplest form, relates the voltage across a conductor to the current through it via V = IR; microscopically it corresponds to a linear constitutive relation J = σ E between current density and electric field for ohmic materials.

A constitutive relation for linear resistive elements stating that the voltage across the element V is proportional to the current through it I with constant of proportionality R (V = I·R). In AC steady state this generalizes to V = Z·I using complex impedance Z; the law applies within the linear regime of the material or device and excludes inherently nonlinear or quantum transport regimes.

A linear constitutive relation for an electrical conductor stating that the potential difference (voltage) V across the conductor is proportional to the electric current I through it, with the constant of proportionality called resistance R (V = I·R); applicable to ohmic, time-invariant conductive elements and used as a local approximation in bioelectric analyses when conductance is linear and cap