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. In a long solenoid, the magnetic field is uniform inside due to the symmetrical arrangement of current-carrying loops, which produce overlapping field lines that are parallel and evenly spaced along the solenoid’s axis, minimizing edge effects in the central region. Substituting values gives The field lines are parallel and evenly spaced, which matches expected magnitude for this magnetic configuration, confirming dipole field