Student Activity Investigating Magnetic Fields

Materials:

• 2 bar magnets (the longer the better)
• Iron filings
• Shaker jars (such as salt shakers)
• Transparency Film/Paper

Hypothesis:

What do you think will happen when similar poles are placed close to each other?

What do you think will happen when opposite poles are placed close to each other?

Procedure:

1. Place a magnet on the table and put the transparent paper over it.
2. Sprinkle iron filings on the paper.
3. Observe the pattern of the magnetic field line. Illustrate what you see. What do you notice about the pattern?
4. Carefully lift the transparent paper up and slide the filings off of into the jar.
5. Place 1 bar magnet on the table and place another bar magnet close by. Place it in such a way that the similar poles are parallel to each other. They should be close enough to attract, but not slide together.
6. Place the transparent paper over the magnets and sprinkle iron filings on them.
7. Observe the pattern of the magnetic field line. Illustrate what you see. What did you notice about the pattern of sprinkles between the poles of the two magnets? What conclusion can be made about charges?
8. Carefully lift the transparent paper up and slide the filings off of into the jar.
9. Once again place one magnet on the table. This time place the second magnet close by in such away that the magnets repel each other. Place them as close together as possible.
10. Place the transparent paper over the magnets and sprinkle iron filings on them.
11. Observe the pattern of the magnetic field line. Illustrate what you see. What did you notice about the pattern of sprinkles between the poles of the two magnets? What conclusion can be made about charges?

Conclusions:

What do you notice about the lines of magnetic force?

What happens when you bring oppositely charged poles of a magnet together?

What happens when you bring like poles of a magnet together?