sähköeristävyyden

Sähköeristävyys, often translated as electrical resistivity, is an intrinsic property of a material that quantifies how strongly that material opposes the flow of electric current. It is the inverse of electrical conductivity. A material with high resistivity is a good electrical insulator, meaning it strongly resists the passage of electricity. Conversely, a material with low resistivity is a good electrical conductor. Resistivity is typically denoted by the Greek letter rho (ρ) and is measured in units of ohm-meters (Ω·m).

The resistivity of a material is dependent on its atomic and molecular structure, temperature, and the presence of impurities. For metals, resistivity generally increases with temperature because the increased thermal vibrations of the atoms impede the movement of electrons. Semiconductors exhibit a more complex relationship with temperature, often showing decreased resistivity as temperature rises due to the increased generation of charge carriers. Insulators have very high resistivities and are used to prevent electrical current from flowing where it is not desired, such as in the casings of electrical appliances or in power lines. The precise measurement and understanding of sähköeristävyys are crucial in the design and development of electrical and electronic devices.