Two long straight parallel wires held vertically have equal but opposite currents as shown in the figure. Which of the following effects will be observed?

Explanation

When two parallel wires carry equal and opposite currents, they create a magnetic field around them. The direction of the magnetic field at any point is given by the right-hand rule. Now, let's consider the magnetic field at points X, Y, and Z. At point Y, the magnetic fields created by the two wires are in the same direction and add up, resulting in a stronger magnetic field than at either X or Z.At point X, the magnetic field due to the current in the left wire is in the upward direction, and the magnetic field due to the current in the right wire is in the downward direction. These two magnetic fields oppose each other, resulting in a weaker magnetic field than at point Y.At point Z, the magnetic field due to the current in the right wire is in the upward direction, and the magnetic field due to the current in the left wire is in the downward direction. These two magnetic fields also oppose each other, resulting in a weaker magnetic field than at point Y.Therefore, the magnetic field at Y is stronger than that at X and Z.