sähkönjohtokykseen

Sähkönjohtokyky, known in English as electrical conductivity, is a measure of a material's ability to conduct electric current. It is the reciprocal of resistivity, meaning a material with high conductivity has low resistivity and vice versa. Conductivity is an intrinsic property of a material, independent of its shape or size.

The phenomenon of electrical conduction arises from the movement of charged particles within a material. In solid conductors like metals, these charged particles are typically free electrons. In electrolytes, ions are responsible for carrying the charge. The ease with which these charges can move determines the material's conductivity. Factors such as temperature, impurities, and the material's atomic structure influence conductivity. For instance, metals generally become less conductive as temperature increases due to increased atomic vibrations hindering electron flow.

Electrical conductivity is quantified using the SI unit siemens per meter (S/m). Materials are broadly categorized based on their conductivity. Conductors, such as copper and silver, have very high conductivity, allowing electricity to flow easily. Insulators, like rubber and glass, have extremely low conductivity, effectively preventing the flow of electric current. Semiconductors, such as silicon and germanium, possess conductivity values between those of conductors and insulators, and their conductivity can be manipulated, making them essential for electronic devices. Understanding sähkönjohtokyky is fundamental in fields ranging from electrical engineering to materials science.