Two long straight copper wires, carrying parallel currents of $$i_1 = 2\ \text{A}$$ and $$i_2 = 5\ \text{A}$$ respectively, lie 10 cm apart in the plane of paper as shown. Knowing that the steady current through a wire produces magnetic field, one can argue that

This is a multiple-correct question, and the correct options are (a), (b) and (c). Wires carrying parallel currents attract each other, because the field of $$i_1$$ exerts a force on $$i_2$$ towards $$i_1$$. By the right-hand rule, an upward current makes its field point out of the paper on its left and into the paper on its right. At O the field of $$i_2$$ (out) is stronger than that of $$i_1$$ (in), since $$i_2 > i_1$$ at equal distance, so the net field is outward; at P both fields point out, while at Q both point into the paper, so (d) is wrong.