Biot Savart Law

It states that the magnetic field strength (dB) produced due to a current element (of current I and length dl) at a point having position vector relative to current element is

where µ0 is permeability of free space. Its value is

 µ0  =  4π × 10-7 CWb⁄A – m.

The magnitude of magnetic field is

where θ is the angle between current element and position vector .

The direction of magnetic field is perpendicular to the plane containing .