What are magnetic field lines? List their properties and draw the field lines around a bar magnet.

1. 1 · Define. Magnetic field lines are imaginary lines that show the direction of a magnetic field; a compass's north pole points along them.
2. 2 · List the properties.
   • N to S outside, S to N inside
   • Closed curves
   • Closer where the field is stronger
   • Never cross each other
3. 3 · Draw the diagram. [Bar magnet labelled N and S; 6 to 8 curved lines with arrows from N to S; lines close together at the poles]
4. 4 · Real life. A compass used by trekkers and sailors lines up along the Earth's field lines.
5. 5 · Close in one line. Field lines show both the direction and the relative strength of a magnetic field.

Scoring tip: Arrows on every line carry marks. Draw the lines close together near the poles.