Practice question

**Bar magnet properties** include dipole moment m = pole strength × separation, unit A·m², field lines emerge from north and enter south outside. Lines never cross, ensuring single valued B at any point, and pattern reflects dipole nature with symmetric loops around magnet. Unlike electric charges, magnetic poles cannot be isolated. Breaking a magnet creates two smaller magnets, each with its own north and south pole, indicating that magnetic monopoles do not exist in nature, a key principle in magnetism. Substituting values gives Magnetic monopoles do not exist, which matches expected magnitude for this magnetic configuration, confirming dipole field dependence on m/r³ and torque relation τ = m B sinθ.