Concept:When two parallel wires carry currents in opposite directions, the magnetic fields generated by each wire reinforce one another in the space between them and partially cancel out in the regions outside them.
Formula:$$ B_{\text{net}} = B_1 + B_2 \quad \text{(in between)} $$
Solution:- Let 'X' be the region directly between the two wires, and 'Y' and 'Z' be the regions outside.
- Using the Right-Hand Rule, the field lines from both wires point in the same direction in region 'X', adding together constructively.
- In regions 'Y' and 'Z', the field vectors from the two wires point in opposite directions, leading to a destructive superposition.
- Therefore, the net magnetic field at 'X' is strictly stronger than at 'Y' and 'Z'.
Why other options are incorrect:Options B, C, and D violate the superposition principle by falsely assuming the fields cancel between the wires or claiming the external fields are stronger.
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