Equal currents of magnitude I travel out of the page in wire M and into the page in wire N. Eight directions are indicated by letters A through H. The direction of the magnetic field at point P is

Question

Equal currents of magnitude I travel out of the page in wire M and into the page in wire N. Eight directions are indicated by letters A through H.  The direction of the magnetic field at point P is

Quizplus · Accepted Answer

By applying the right-hand thumb rule, we can determine the direction of the magnetic field at point P. The magnetic field lines will form concentric circles around the wires, with their direction being tangent to the circles. For wire M, the magnetic field at point P will point clockwise (looking from M towards P), and for wire N it will point counterclockwise (looking from N towards P). The magnetic fields due to M and N will add up at point P, resulting in a net magnetic field pointing towards the left, as shown in option C.

Equal Currents of Magnitude I Travel Out of the Page