MAGNETISM

Station A – What kinds of materials are magnetic?

Instructions:

1. Copy the question above.

2. Make the chart below.

3. Fill in the prediction for all the items first, then test each item by touching them with a magnet.

Item / Prediction:
put M for magnetic
put NM for not magnetic / Actual
put M for magnetic
put NM for not magnetic
Washer
Foil
Tin can
Plastic spoon
Wooden popsicle stick
Steel nail
Copper Wire
Battery
Pencil lead
Cardboard
List an item of your choice
______

*Use BYOT to look up what pennies were made of before 1980 versus after 1980.

4. Write a rule that you think explains what kinds of materials are magnetic and what kinds are not.

5. Go to pages 655 and 665 in the blue textbook. Copy and answer the following:

What is a magnet? (page 655)

What is a ferromagnetic material? (page 665)

What are 4 common ferromagnetic materials? (page 665)

What is an “alnico magnet?” (page 665)

MAGNETISM

Station B – Magnetic Force

What is the force of magnetism like?

Instructions:

1. Copy the question above.

2. Draw the table below.

3. Place the two small bar magnets on opposite ends of a sheet of paper.

4. Slowly slide one magnet toward the other until it moves. Measure the distance between the two magnets when this happens and record

5. Turn on magnet around 180o. Repeat the activity. Then turn the magnet and repeat again.

6. Repeat the activity with one magnet perpendicular to the other, in a T-shape.

Ends of the magnets / Distance apart when the one magnetmoves
N and S
N and N
S and S
T shape

7. Copy and answer the following questions:

How close did the magnets have to be to affect each other?

How did the forces exerted by the magnets change as the magnets were moved closer together?

(Read page 656 in the text) What is a magnetic force?

Identify which attract or repel:

N to N ______

S to S ______

N to S ______

8. Tie a string to a magnet. Dangle it and see which direction the north pole of the magnet points to. Use a compass on a smart phone to verify the direction.

MAGNETISM

Station D – Magnetic fields

What are magnetic fields?

Instructions:

1. Copy the question above.

2. Shake the thin plastic box with iron filings in it so that the filings are scattered evenly in the box. Place it over one end of the magnet. Note how the filings “line up” and swirl around the ends of the magnet. Move the plastic box down the magnet and watch how the filings line up.

3. Place a bar magnet on the table and make sure all other magnets are at least 2 meters away from it. Place the small compass on the table, up against the bar magnet at one end. Move the compass around the magnet at 1 cm “steps.” The compass should be touching the magnet. Note the direction of the needle and how the direction changes.

4. Move the compass 2 cm out from the magnet and repeat the process. What do you notice? Do it again at 4 cm and the 6 cm from the magnet.

5. Go to page 657. Do the magnetic field lines in the diagram follow the direction the compass needle was pointing? Draw a picture of a magnet and the magnetic field lines around it. Be SURE to include the arrow heads to show the direction of the magnetic field. Label the poles.

6. Using page 657 copy and answer the following questions:

What is a magnetic field?

What are magnetic field lines?

What direction do the magnetic field lines flow?

How is the strength of the magnetic field shown with the lines?

Where is the magnetic force the strongest?

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What do the magnetic field lines look like when magnets interact?

Instructions:

1. Copy the question above.

2. Shake the thin plastic box with iron filings in it so that the filings are scattered evenly in the box. Put 2 magnets with opposite poles end to end and place the plastic box over the ends of the 2 magnets. Pull the magnets apart and watch how the pattern of the filings change. (over)

3. Shake the plastic box again, scattering the filings. This time put the 2 magnets with like poles end to end and place the plastic box over the ends of the two magnets.

4. Go to page 659 and use the illustrations to draw the two kinds of pole interactions: attraction and repulsion. Be sure to label the poles.

5. There is a GREAT “Active Art” in our textbook about this if you are able to get to it with our smart phone or tablet.

MAGNETISM

Station C – Domains

What happens if a magnet is broken into two pieces?

Instructions:

1. Copy the question above.

2. Investigate the piece of broken magnet with the unbroken magnet. What do you notice about the “polarity” (what the poles are) of the broken magnet? Are the same poles, different poles? Draw a picture of the broken magnet and label the poles. What could be an explanation?

3. Read page 664 and copy and answer the following questions?

Why are most materials not magnetic?

What is a “magnetic domain?”

What makes a magnetized material?

(Go to page 665) Draw 2 pictures: the domains in a magnetized material and the domains in a non-magnetized material. Be sure to label them.

Why would heating or dropping a magnet demagnetize a magnet?

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How can I make a temporary magnet?

Instructions:

1. Copy the question above. Copy the table below.

Student names / 0 strokes / 50 strokes / 100 strokes

2. Steel contains iron. Check to see if a steel paper clip is magnetic. Will it pick up other paper clips? Try to magnetize a steel paper clip by rubbing it in one direction along one pole of a magnet 50 and then 100 times. See how many other paper clips you are able to pick up with the paper clip. What must happen to all the paper clips along the chain?

3. Will the paper clip stay magnetic forever?

4. Use page 666 to write the definitions for “temporary magnet” and “permanent magnet?”

5. Copy and answer this questions: What must happen to the domains in a temporary magnet?