<Dl> <Dd> v = Γ 4 π r (cos ⁡ A − cos ⁡ B) (\ displaystyle v = (\ frac (\ Gamma) (4 \ pi r)) \ left (\ cos A - \ cos B \ right)) </Dd> </Dl> <Dd> v = Γ 4 π r (cos ⁡ A − cos ⁡ B) (\ displaystyle v = (\ frac (\ Gamma) (4 \ pi r)) \ left (\ cos A - \ cos B \ right)) </Dd> <P> where A and B are the (signed) angles between the line and the two ends of the segment . </P> <P> In a magnetostatic situation, the magnetic field B as calculated from the Biot--Savart law will always satisfy Gauss's law for magnetism and Ampère's law: </P>

Biot-savarts law states the relation between magnetic intensity and