Final answer:
The magnitude of the magnetic force between two parallel power lines carrying currents can be calculated using the formula involving the permeability of free space, currents in the wires, and separation between the wires; wires with parallel currents exert an attractive force on each other.
Step-by-step explanation:
The question asks about the magnetic force between two power lines that run parallel to each other, each carrying a current. The formula for the magnetic force per unit length (F/l) between two parallel conductors is given as:
F/l = (0 * I1 * I2) / (2 * d)
where μ0 is the permeability of free space (4 * 10^-7 T·m/A), I1 and I2 are the currents in the wires, and d is the separation between the wires. Using the given values and this formula, the force per meter can be calculated. When currents are in the same direction, the force is attractive, pulling the wires together. If they are in opposite directions, the force becomes repulsive, pushing the wires apart. For the given scenario, currents are parallel, thus the force would be attractive.