Sähköjohtavuutena

Sähköjohtavuutena, also known as electrical conductivity, is a measure of a material's ability to conduct electric current. It is defined as the reciprocal of electrical resistivity and is typically expressed in units of siemens per meter (S/m). Materials with high electrical conductivity, such as metals like copper and silver, allow electric current to flow easily. Conversely, materials with low electrical conductivity, like insulators such as rubber and glass, impede the flow of electric current.

The electrical conductivity of a material depends on several factors, including its composition, temperature, and the presence of impurities or defects. In metals, electrical conductivity is primarily due to the movement of free electrons. As temperature increases, the thermal energy causes these electrons to move more freely, resulting in higher electrical conductivity. In semiconductors, electrical conductivity can be controlled by doping, which introduces impurities to create a higher concentration of free charge carriers.

Electrical conductivity is a crucial property in various applications, including electronics, power transmission, and heat management. Understanding and controlling electrical conductivity is essential for designing and optimizing electrical devices and systems.