Final answer:
The magnitude of the magnetic force on a wire can be calculated using the formula F = B * I * L. In this case, the magnetic field created by the two outer wires can be calculated using Ampere's Law. Plugging in the values will give you the magnitude of the magnetic force on the wire.
Step-by-step explanation:
The magnitude of the magnetic force on a wire can be calculated using the formula:
F = B * I * L
Where F is the magnetic force, B is the magnetic field, I is the current, and L is the length of the wire.
In this case, the magnetic field created by the two outer wires can be calculated using Ampere's Law:
B = (μ0 * I) / (2π * r)
Where μ0 is the permeability of free space, I is the current, and r is the distance from the wire.
Plugging in the values, the magnetic force per meter on either of the outer wires is:
F = (2 * 10-7 Tm/A * 20 A * 0.5 m) / (2π * 0.04 m)
Calculating this will give you the magnitude of the magnetic force on the wire.