sähköjohtavan

Sähköjohtava refers to the property of a material to conduct electric current. This conductivity is due to the presence of mobile charge carriers, which are typically electrons in metals and ions in electrolytes. The degree of conductivity varies greatly among different materials. Metals like copper and silver are excellent conductors, meaning they offer very little resistance to the flow of electricity. This is why they are commonly used in electrical wiring. Semiconductors, such as silicon and germanium, have conductivity between that of metals and insulators. Their conductivity can be controlled by doping, which involves adding impurities to the material, making them crucial components in electronic devices. Insulators, like rubber and glass, have very few free charge carriers and thus exhibit extremely low conductivity, making them useful for preventing electrical current from flowing where it is not desired, such as in the casing of electrical appliances. The SI unit for electrical conductivity is siemens per meter (S/m). Conductivity is the reciprocal of resistivity, which measures a material's opposition to electrical current flow. Factors like temperature and the presence of impurities can significantly influence a material's electrical conductivity.