CHEMISTRY GLOSSARY

The magnetic field B due to a current-carrying conductor can be determined by Biot-Savart law. The contribution to magnetic field set up at distance r by the current element IdL is given by expression:

where μ₀ is permeability constant. It plays a role in magnetic problems equivalent to the role of permittivity constant μ₀ in electrostatics problems. In order to obtain B, contributions of all current elements have to be integrated. In case of a long straight conductor, carrying current I, Biot-Savart law gives:

SI unit for magnetic field B is tesla (T).

Permaeability constant μ₀ has value 4π×10^-7 T m A^-1.