Investigating Magnetism

DSVS Spring 2011Eighth Grade

Lab 1

Introduction

• Introduce yourself• Explain what DSVS is and what it aims to do• Spend time engaging the students in conversation

about science, college, Davidson, etc.• Spend a maximum of 30 minutes on this before

beginning the labs• Tailor this presentation to the needs and interests

of the class. If they’re bored, move on.

The Activities

• Suggested Activities for Magnetism are – 4. Making a Magnet– 5B. Directional Properties of Magnets– 7. Magnetic Fields– 8. The Interaction of Magnetic Fields

Be prepared to cut activities if you run out of time.

All this information can be found in the student worksheets and instructor guide that comes with your equipment kit.

Preliminary Discussion

• Ask: What substances will a magnet attract?– Answer: Substances made of iron, steel, nickel and

cobalt

• Ask: Are all parts of a magnet able to attract with equal strength?– Answer: No. The ability to attract is centered in

each end of the magnet. These are called the poles.

4. Making a Magnet (A)

• Have the students rub one end of a bar magnet on a steel needle

• They must go in the same direction each time, using the same side of the magnet

4. Making a Magnet (A)

• Have them test if the needle is magnetic by holding it near another uncharged needle

4. Making a Magnet (B)

• Begin by assembling the battery.

• Use size four, size D batteries. Insert them in the plastic sleeve.

• Insert one of the metal tabs between each battery

• Tape the two at the ends

4. Making a Magnet (B)

• Wrap a nail in the copper wire.

• Leave a tail off each end• Strip the ends of the

copper wire, scissors work just fine.

• Students will likely need help with this.

• You might consider doing this for them ahead of time.

4. Making a Magnet (B)

• Hook the nail to the battery, completing the circuit as shown.

4. Making a Magnet (B)

• Have the students tests the nail for magnetism.

• Explain the relationship between current and magnetism.

5B. Directional Properties

• Have the students charge a needle as in 4A.

• Tape it to the cork and set afloat in water.

5B. Directional Properties

• Compare the direction of the needle to a compass.

• What happens when a magnet is placed near the needle?

Discussion Questions• Did the magnet always come to rest in the same

direction?– Yes

• Which direction is the magnet pointing in according to the compass?– It points in a N-S direction.

• Did the needle act like a compass?– Yes

• Why is it important to make sure the magnet is far away from the compass?– The magnet will attract the compass.

7. Magnetic Fields

• Place a magnet in a plastic bag on top of a brightly colored piece of paper.

• Scatter iron filings over the top.

• Tell students not to waste the filings.

• What does the pattern mean?

8. Interactions of Magnetic Fields

• Repeat, this time using two magnets with opposite poles near.

• Try several arrangements of the magnets.

Discussions Questions

• Have students draw the field lines shown by the iron filings.

Wrapping Up

• Clean Up• Discuss the experiments with the class.• Answer any student questions.• Conclude the lesson.• Remind them you’ll be back next month.

References

These activities and discussion questions are from:• “Investigating Magnetism”• John M. Rogan, Pd.D., Western Montana College• Hubbard Scientific Inc. Chippewa Falls, Wisconsin

Training slides and photos• Lerin Rutherford