The Biot-Savart law for the magnetic field has certain similarities, as
well as, differences with the Coulomb’s law for the electrostatic field Some
of these are:
(i)
Both are long range, since both depend inversely on the square of
distance from the source to the point of interest The principle of
superposition applies to both fields [In this connection, note that
the magnetic field is linear in the source I dl just as the electrostatic
field is linear in its source: the electric charge