Experiências de magnetismo de baixo custo

In this video I'm going to show you how you can do different magnetism experiments. In order to visualize the magnetic field strength lines of two magnets I'm going to place iron filings on both sides of a tray. Now I'm going to position the two magnets so their north is pointed inward.

So I'm going to sprinkle iron filings all over the tray and that's how the iron filings align with the magnetic field formed by the two magnets. As the two magnets tend to repel each other, so the magnetic field lines formed by them also tend to pull apart. This means that if I flip one of the magnets, then they tend to attract.

And that's why this time you can see that the magnetic field lines tend to meet in the center of the tray. To build this experiment I went to a sawmill and asked to collect some iron filings that were splattered on the floor. Then I passed a sieve to be able to discard the larger particles and then I threw away the thicker iron filings because what really interests me is the iron powder that gives this impression of fluid iron.

As I didn't know if the iron powder could be mixed with aluminum powder or even dirt so I did a separation process using a container with a magnet. What was not ferromagnetic was not attracted to the magnet, so it was discarded. Then I repeated the process several times and kept it in a salt shaker.

I also needed a plastic tray in which I placed two wooden feet underneath it to suspend the tray. Then I got one of those speaker ferrite magnet from the junkyard and I broke it into two smaller pieces. To find out which was the north pole of the magnet I went to see which part of it attracted the south of the compass, then I put a masking tape to be able to paint it red and signal which was the north pole of the magnet and now it's done our experiment.

It is also possible to visualize magnetic field lines in 3D by doing an experiment like this. This three-dimensional visualization can also be done inside a transparent container that contains mineral oil. Inside this container I put burnt Bombril powder and also a marble to serve as a mixer.

Now I'm going to put on both sides of the container a neodymium magnet which is also known as a super magnet. Since the magnets are poles apart to the inside, you can see that the magnetic field lines are interconnecting on both sides and this is because the two magnets attract each other. Now I'm going to repeat the experiment by reversing the poles of one of the magnets and then you can see the magnetic field lines forming, but now inside you can see that the lines tend to move apart.

That's because the magnets are repelling each other. Now I'm going to show you a series of magnetic levitation experiments. The first one can be made with the magnet, a paper clip and a string.

The clips don't attract each other, but if I put one of them close to a magnet, then it will temporarily become magnetized. Another thing that can be done is to put several of these speaker magnets into a hose. Between them the poles need to be the same to be able to repel and levitate.

Finally I'm going to show you how you can use a compass. Notice that north is pointing there and that means if in front of me is north, on my right side I have the rising sun in the east. If I'm in the southern hemisphere then the sun will tilt to the north and set on my left side in the west.

If you don't have a compass, you can also use a magnet with a string, check it out. Notice that it lined up exactly where my compass was pointing. One of the great advantages of having a compass in your hand if you got lost in a forest, for example, is that you won't be able to follow the sun's trajectory if this forest was too dense and it can be useful to help you walk in a straight line.

preventing you from getting lost by going around in circles. And if you liked this video, subscribe to the channel and activate the bell to receive notifications of upcoming videos. Bye!