Force Calculation

The force per unit length between two parallel current-carrying wires is given by:

F/l = (μ₀ I₁ I₂) / (2π r)

F = (4π×10⁻⁷ × 8.0 × 5.0 × 0.1) / (2π × 0.04) = 2.0 × 10⁻⁵ N

Where:
μ₀ = permeability of free space (4π×10⁻⁷ N/A²)
I₁ = current in wire A (8.0 A)
I₂ = current in wire B (5.0 A)
r = distance between wires (0.04 m)
l = length of wire section (0.1 m)

The force is attractive when currents are in the same direction, and repulsive when in opposite directions.