Difficulty of realization 7/10
Step 1: How to Make
I wanted to make this experiment to visualize the magnetic field lines in 3D.
We've all played by guys with iron filings moved by a magnet under the table, with this game you have already an idea of the shape of the magnetic field, but, putting the iron filings in a fluid, you have a better perception of shape of the magnetic field. In fact the iron filings is slowed down by the fluid giving the time to observe it while moving on the magnetic field lines.
For this experiment is required a very fine iron filings, otherwise it falls too fast on the bottom of the bottle. For this reason I decided to try to get me alone filing by an iron rod and with the help of a grinder . I then combed the filings with very fine strainer kitchen to eliminate biggest filings pieces. Finally I put the filings in water to wash impurities. After shaking the jar is easy to separate filings dirt approaching a magnet to the can, the dirt remains in suspension and can be eliminated easily. Do at least ten rinses.
Now you have to choose a bottle, it should be transparent and it is better that it is narrow and long. Fill it with water and put into the filings.
Step 2: Plays With It
If you have a nice collection of magnets this is the time to take them out for everyone to see the shape of the field.
For still slow down the movement of the filings can replace the water with different types of oil, the best believe that it is the silicone oil, transparent and dense at the right point. Also dipping filing in oil prevents oxidation.
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