Field Lines

1. Identify the source magnet. 2. Show lines leaving the north pole and entering the south pole. 3. Make lines denser where the field is stronger. 4. Never draw lines crossing. 5. Add arrow direction if required.

Draw a bar magnet with several smooth curved lines from N to S. Show denser lines near the poles and wider spacing farther away.

A common wrong answer is to draw straight parallel lines around a bar magnet. That does not show the actual curved magnetic field pattern.

Field lines are imaginary lines used to show the shape, direction, and strength of a magnetic field.

Field lines are imaginary lines used to show the shape, direction, and strength of a magnetic field. Field lines outside a magnet go from north pole to south pole, and no two field lines intersect each other. Around a bar magnet, the lines curve from the north pole to the south pole and do not intersect each other.

Field lines help us read a magnetic field visually. They start from the north pole outside a magnet and enter the south pole. Where the lines are closer, the magnetic field is stronger. Where they are farther apart, the field is weaker. In the lab and in diagrams, field lines help students understand how a compass would align in different positions. Field lines outside a magnet go from north pole to south pole, and no two field lines intersect each other. If a compass is moved from the middle of a bar magnet to near its pole, the needle shows a larger deflection near the pole. This matches the diagram, because field lines are denser there. Draw magnetic field lines around a bar magnet, or state what field-line spacing tells us about strength. A common wrong answer is to draw straight parallel lines around a bar magnet. That does not show the actual curved magnetic field pattern.