Ampere's force law presents that the force of attraction or repulsion between the two wires carrying currents is equivalent to their lengths and the magnitude of current passing through them. If the currents run in a corresponding direction, repulsion takes place. The physical beginning of this force is that each wire produces a magnetic field.
The magnetic field in the space surrounding an electric current is comparable to the change which serves as the source. Ampere's law asserts that for any closed loop path, the sum of the length elements times the magnetic field is equivalent to the permeability times the current.