Discovery 1: Discovering Magnetic Properties and Fields
Directions: Answer all questions in compete sentence and spend no longer than 10 minutes at each station.
Station 1: Observing Magnet Fields on a TV Screen
Procedure:
1) Q: Bring the magnet near the screen. What happens to the screen as the magnet approaches?
2) Q: Place one magnet on the screen and describe what you see.
3) Q: Why do you believe the screen shows these patterns or distortions?
4) Q: Are there other places on the TV you can position the magnet such that so that these distortions appear?
5) Rotate the magnet on the screen to further observe the magnetic field.
6) Q: Bring two magnets near the screen and observe the patterns. Do the magnetic fields seen to interfere with each other and if so, how?
Station 2: 3-D Magnetic Fields with Iron fillings
Procedure:
1) Q: Place one magnet on the plate and allow the fillings to build on the magnet. Draw a 2D picture of the field around the magnet:
2) Place a second magnet in the iron filings and bring it near the first magnet.
a) Q: What happens to the filings when the magnets repel? Pictures help!
b) Q: What happens to the filings when the magnets attract? Pictures help!
3) Q: What part of the magnet appears to be the north pole and south pole? Hint: Look at the part of the magnet where the fillings are merging into.
4) Q: Draw a picture of the magnetic fields around the magnets when they are attracting and repelling:
Station 3: Materials that Attract to and Repel from Magnets
Procedure: Make a list of the materials provided that fall under the following categories. If the attraction or repulsion is so weak, hang the material from a string and then bring the magnet near it to observe subtle movements. On you sheet of paper, label the following magnetic states along with the materials that correspond to it.
1) Q: Ferromagnetism: Materials that strongly attract
2) Q: Paramagnetism: Materials that weekly attract
3) Q: Diamagnetism: Materials that repel
Station 4: Magnetizing Metal
Procedure:
1) Q: See if a magnet can cause other materials to become magnetized by placing the magnet directly on the material and then dipping the material in the iron filling. What materials were able to become magnetized?
2) For the materials that do become magnetized by the magnet:
a) Q: Do they stay magnetized after the magnet is pulled away? Use the iron filling to check.
b) Q: What happens to the strength of the magnet over a period of time?
Station 5: Making a compass
Read the article: http://www.ocean.washington.edu/people/grads/mpruis/magnetics/history/hist.html
1) Q: Who was the first civilization to discover magnets?
2) Q: How was the first compass made?
Making a compass:
3) Perfectly place the magnet in the center of the floating dish and stand it on various sides until the floating dish forcefully takes a direction. You have just made a compass. The magnet now aligning with the earth magnetic field.
4) Q: Bring a second magnet next to your compass and observe what happens. Why does the compass begin to rotate in other directions?