Question

By symmetry, the magnetic field of conductor b exerts a force on conductor a. The relationship between the two forces Fba and Fab is:

Options

• \[\vec{F}_{ba} = 2\vec{F}_{ab}\]

• \[\vec{F}_{ba} = -\vec{F}_{ab}\]

• \[\vec{F}_{ab} = 0\]

• \[\vec{F}_{ba} = \vec{F}_{ab}\]

Answer 1

By symmetry, the magnetic field of conductor b exerts an equal and opposite force on conductor a: Fba = (μ₀IaIb/2πd)·L and Fba = −Fab. This confirms Newton's Third Law — the forces are equal in magnitude and opposite in direction.