Attraction of two wires
A current-carrying wire acts as a source of magnetic field. A second wire will feel a force from the magnetic field of the first one. The force on wire a due to wire b will always be equal in magnitude and opposite in direction to the force on wire b due to wire a (Newton's third law). Using the right-hand rule you can show the following:
Parallel wires with currents flowing in the same direction, attract each other.
Parallel wires with currents flowing in the opposite direction, repel each other.
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