Konduktiioon

Konduktiioon is the process by which energy, a signal, or a substance is transferred through a medium due to a driving force or gradient. The term is used across physics, engineering, and biology to describe related transport phenomena. In each context, konduktiioon involves a medium that supports transfer and a measurable response that depends on material properties and geometry.

Electrical konduktiioon occurs when charge carriers move under an electric field. In metals, free electrons drift; in electrolytes, ions carry charge; in semiconductors, electrons and holes contribute. The relation between current and voltage is captured by Ohm's law: I = V/R (or J = σE, with σ the conductivity). Conductivity depends on temperature, impurities, and structure; superconductors are a special case with vanishing resistance below a critical temperature.

Thermal konduktiioon is the transfer of heat through a medium due to a temperature gradient. Fourier's law q = -k ∇T uses k, the thermal conductivity. Materials with high k (metals) transfer heat efficiently; insulators have low k. Heat transfer arises from lattice vibrations (phonons) and molecular motion, with convection contributing in fluids.

Biological konduktiioon refers to the propagation of electrical signals in living tissue, notably nerve impulses and muscle action potentials. Neurons transmit signals via ion channels, creating rapid changes in membrane potential. Myelination increases conduction speed through saltatory conduction.

Understanding konduktiioon aids the design of electronic devices, thermal management, medical diagnostics, and neuroscience. It is distinguished from diffusion by its directional transfer driven by a gradient or field, rather than random motion. Field-specific terminology varies, but common themes include dependence on medium properties, geometry, and boundary conditions.