Magnetizing is Awesome!

One day, just a few weeks ago, we did a science kit. It was a magnet science kit. The kit had seven experiments. They all had to do with one of the four magnets that came with it.

Here are some pictures from when I did that:

10 items 1 magnetizeation

This is 10 items but only 1 is magnetic. It’s the scissors!!!!!!!!

magneto car.

This car can be driven by a magnet. VRRRRROOOM VROOOM!!!!!!!!!!!!

iron filings face + magneto car

Do you see magneto car? That’s me making a iron filing face behind it. WOOT!

testing 1 2 (magnet version)

This is me trying to pick up a pen with a magnet. FAIL!

notes notes notes la la notes

This is me taking notes.

compass time!!!!!!!!!!!!!!!!!!!!!

This is me looking at a compass I just made.

filings 1

This is a really interesting iron filing picture.

filings 2

This is another really interesting iron filing picture.


Peo’s Questions

 

  1. How do magnets work?
  2. How do poles stick to each other?
  3. And why do poles that are alike repel?

6 comments

  1. Rugger Ducky says:

    Hi Peo,

    I have always been fascinated by magnets. They work because of the magnetic field that surrounds the Earth. It is closest to the poles of the Earth (http://goo.gl/1QGyH has a good picture of it). Magnets are pieces of metal charged to the magnetic field of the Earth, and as a result, if allowed to, will orient themselves to a North/South turn.

    Magnets can be found naturally charged in the environment, or by using electricity. Certain atmospheric phenomena, like Aurora Borealis (https://www.youtube.com/watch?v=FcfWsj9OnsI) are actually cost by interference in the magnetic field. The interference is usually caused by solar flares, which are huge bursts of energy cast off by the Sun as it creates and expels sun spots.

    The poles that are alike repel each other, and the opposite poles attract because of the old rule “opposites attract”. Ask your parents about that one. Sir Issac Newton wrote a lot about it, as did the early Greeks.

    The interesting thing to think about next is how magnetics eventually created computers. Yes, that’s right, the computer you’re reading this on is storing it and sending it along using huge numbers of magnetic writing. A standard hard drive uses a magnet turned into a spinning disc. As data is written to the drive, it is written in a series of 0s and 1s. Each represents one pole of a magnet. To write a single bit of data, a 0 or a 1, in binary code, the hard drive actually uses another magnet to flip the polarity of the bit of data being “written” to. It is really just a bunch of magnetic on and off switches.

    • Rugger Ducky says:

      eep– “are actually cost by interference” should be “are actually caused by interference”. Spellcheck hates me some times. Sorry Peo!

    • Peo Webster says:

      Wow! I did not know that computers ran on magnets. Thanks. 😉

      • Rugger Ducky says:

        Have you ever seen the inside of a hard drive? If you want to try it, be sure to have your Mom or Dad help, and make sure it is a drive you don’t ever want to use any longer. They’re hard to open up, and need special screwdrivers. Also, the magnets inside are very strong, and can easily pinch your finger snapping together when you’re trying to take apart the drive.

  2. Mike D. says:

    Umm, no… the Earth’s core is a giant magnet, sure, but magnets aren’t dependent on the Earth to work.

    A magnetic field is caused by the motion of electric charge. That’s it. There are these equations known as Maxwell’s Equations that describe it, but the simple explanation is what we call the right-hand rule: Take your right hand and make a thumbs-up gesture with it. When an electric current moves in the direction of your thumb, it creates a magnetic field that moves in the direction of your curled fingers.

    Now if you could move your hand in a circle, turning your thumb to face forward as you move it (don’t try it; wrists don’t pivot like that), you’d notice that the fingers on the inside of the curve point one way and the ones on the outside point the other way. (I *really* need a whiteboard to draw this. >_<)

    Now think about atoms, with those electrons spinning around their nuclei. The atoms are electric charges, and they create little currents by moving, so when they move in circles, they make little magnetic fields. If all the circles are randomly ordered, these fields mostly cancel out, which is why most things aren't magnetic.

    But some atoms — iron, manganese, and cobalt — aren't as random, and their electrons *like* to line up in circles (yeah, I'm oversimplifying this). They're called "ferromagnetic". The ferro- part comes from "ferrite", an old word for iron (and why iron's chemical symbol is Fe).

    What this means is that, if you just have some iron filings, they're not magnetic by themselves because their fields are pointing all random directions. But when you bring a magnet near, they spin around and move where they can to align themselves with the field. This is called "magnetization." If you do this while the iron is really hot, like in a furnace, then keep the magnetic field in place while it cools, the iron atoms will stick in this aligned position and become a magnet.

    So why do they attract and repel? Well ,when you make a magnet, the lines of magnetic flux (your curled fingers in th right-hand rule) are all coming out one end, looping around, and going back in the other. When you bring two magnets together, if the ends that are near each other are opposite poles, their lines will link up (need that whiteboard again) and they'll pull together. If the ends are the same poles, the flux lines can't link up and instead bunch up, pushing off of each other. The force they push with is related to how many of these lines are packed inot an area; more lines, more pushback.

    Anyway, there's only a couple more steps from here to "how electric motors work", but I'll stop now before your Mom hurts me.

    There was a guy named Michael Faraday who lived long ago who figured a lot of this out, without even knowing about how atoms played into it. Read up on his work some year; the ways he figured these things out were really cool, since he used visual descriptions more than math equations.

    Fun fact: the Voyager space probe (which is the farthest man-made object from Earth) has magnetic field sensors that are currently measuring the magnetic field between the solar system and interstellar space, and it has been seeing some rather interesting effects.

    Another fun thing: water is magnetic. The water molecule is a little bit lopsided, which gives it a really weak field. Normally you don't notice this, but if you get a strong enough magnet and place it near water running out of a faucet, it can deflect the water a bit.

  3. Mike D. says:

    Oh, hey, someone already did these diagrams. Don’t bother with the equations, just look at the pictures.

    First, the right-hand rule: http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magcur.html

    Second, bending the current into a loop to get a magnetic field with poles: http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/curloo.html

    Third, the fields of opposite poles linking up: http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magfor.html#c3

    Bonus: comparison of things that make magnetic fields, or how the Earth is just a bid old magnet: http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magfie.html#c1

    P.S. The Earth’s magnetic field? The Earth’s core is made of… iron! And it’s plenty hot enough to line all that iron up. And sometimes, the Earth’s field flips over, swapping North with South!

Leave a Reply