Two long, parallel wires each carry the same current I = 2.00 A, pointing in opposite direction (see figure below). The two wires are 0.200 m apart. What is the total magnetic field at the point P midway between the wires?
This question can be done even without the figure only the direction cannot be acsertained..Since magnetic field vector is perpendicular to both current and direction vector, the magnetic field vector at the required point is perpendicular to the plane of paper that is it is either coming out of the plane or is directed inside the plane.Now by using Fleming's Right hand corkscrew rule,the magnetic at the mid point is added up due to the opposite direction of current in each wire.Therefore the total magnetic field at the mid point is:
here the distance applied in formula is half of the distance between the wires
Now putting the values we get magnetic field as 8x10-6Tesla