Magnets and electromagnets Lesson 2

2. Magnetic Fields - Experiment Put a magnet under a piece of paper. Carefully scatter iron filings on the paper. Draw what you see.

3. What is a magnetic field ? The iron filings locate the magnetic field and show the direction of the forces in this region. The region around a magnet where it has a magnetic effect is called its magnetic field. If you put a magnetic material in that field it will experience a force. N S

4. Magnetic Fields What does the magnetic field around a bar magnet look like ? [shape and direction]. N S Strongest at poles Weaker further away

5. Drawing a magnetic field

6. Magnetic field lines From N to S N S Notes

7. Magnetic Fields - Experiment Put the north and south poles of two bar magnets together. What happens? Now put the two magnets under a piece of paper with N and S poles together. Carefully scatter iron filings on the paper. Draw what you see.

8. Magnetic field pattern with N and S poles together N N S S Notice the pattern of lines of force in this region. How are they different from a single magnet’s field?

9. ATTRACTING Notes

10. Magnetic field pattern with N poles together N N S S Notice the pattern of lines of force in this region.

11. REPELLING Notes

12. Magnetic Fields - Summary 1. When two like poles (two North poles or two South poles) are put together, they repel each other. 2. When two unlike poles (a North and a South pole) are put together, they attract each other. 3. Scattering iron filings around the bar magnets allows us to see the lines of force of the magnetic field. A plotting compass allows us to draw the field. Notes