Concept:When two parallel wires carry currents, they exert a magnetic force on each other. If the currents are in the
same direction, they attract.
Formula:$$ \frac{F}{L} = \frac{\mu_0 I_1 I_2}{2\pi d} $$
Solution:- The magnetic field created by one wire at the location of the other can be found using the right-hand rule.
- Applying Fleming's left-hand rule (or \( \mathbf{F} = I(\mathbf{L} \times \mathbf{B}) \)) shows that the force on each wire points towards the other wire.
- Because they are free to move, the attractive force will cause them to move towards each other.
Why other options are incorrect:Option A ignores the existence of the magnetic force. Option C would happen if the currents were in opposite directions. Option D is physically impossible for parallel uniform fields.
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