<P> These equations are called the "Biot--Savart law for a point charge" due to its closely analogous form to the "standard" Biot--Savart law given previously . These equations were first derived by Oliver Heaviside in 1888 . </P> <P> The Biot--Savart law can be used in the calculation of magnetic responses even at the atomic or molecular level, e.g. chemical shieldings or magnetic susceptibilities, provided that the current density can be obtained from a quantum mechanical calculation or theory . </P> <P> The Biot--Savart law is also used in aerodynamic theory to calculate the velocity induced by vortex lines . </P> <P> In the aerodynamic application, the roles of vorticity and current are reversed in comparison to the magnetic application . </P>

Explain biot savart law and its applications pdf