Student Exploration: Magnetism
Vocabulary: attract, bar magnet, ferromagnetic, magnetize, north pole, repel, south pole
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
What happens when you place two magnets close together?
What objects do magnets stick to? Make a list.
What do these objects have in common?.
Gizmo Warm-up: What is attracted to magnets?
A bar magnet is a simple rectangular magnet. If you hang a bar magnet by a string, the north pole (N) of the magnet will tend to point north while the south pole (S) of the magnet points south.
Look at the materials at the bottom of the Gizmo™. Which ones do you think will stick to a bar magnet?
Ferromagnetic materials are strongly attracted to magnets. Drag a bar magnet and the piece of nickel onto the scribbled line. Press Play ().
A. Is nickel ferromagnetic?
B. How do you know?.
Test copper, wood, glass, and iron. Which ones are ferromagnetic?
Attract or repel?
Get the Gizmo ready:
Check that the MAGNETIC FORCES tab is selected.
Click Reset ().
Question: How do magnets interact?
Observe: Drag two bar magnets onto the paper and press Play. Then click Reset. Change one of the magnets (either from N-S to S-N, or vice-versa). Click Play again.
What happened the first time?.
What happened the second time?.
Form hypothesis: Magnets are either pulled together (attracted) or pushed apart (repelled). Based on what you have seen, when are magnets attracted and when are they repelled?
Predict: Based on your hypothesis, which pairs of magnets will be attracted to each other? Which will be repelled? Record your predictions below. (Leave the result blank for now.)
Run Gizmo: Test your predictions using the Gizmo. Record your results in the table.
Draw conclusions: Fill in each blank below with the correct word.
The south pole of a magnet is attracted to the pole of another magnet.
The south pole of a magnet is repelled by the pole of another magnet.
The north pole of a magnet and the north pole of another magnet will each other.
Magnetic field lines
Get the Gizmo ready:
Click Reset and drag all objects off the paper.
Select the MAGNETIC FIELD LINES tab.
Question: If you scatter iron filings (little slivers of iron) around a magnet, you will see a pattern of magnetic field lines. What do these lines show you?
Observe: Drag one magnet onto the paper. Click Sprinkle filings and then Tap