Science Buddies: "Ask an Expert"

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This is a project I have actually created and finished. However, I made tiny adjustments. Instead of making an adjustable wall, I have one that can only stay in one place. I have also replaced the coins with different sized metal washers. (This is because we are suppose to make it out of "odds and ends" and I had a lack of material. The magnet is provided.)

However. I am still a little confused as to what the point of this project even is. (I know it's kind of stupid for me to think of that now that i've actually made it and it's too late to change because it's due tommorow askjdfhkashsdf).

I mean, the washers are ALREADY able to magnetize, so what exactly makes walking it up and down the wire so special? What point does it make? The only thing I have observed it that some sized washers go up and down smoother than others.

So basically, my question is. What is the physics behind this? What makes "walking" up and down the wire so important? I'm guessing it has something to do with magnetic fields and flux lines, but i'd like to know the exact explanation of physics regarding this.

Thank you for your time and effort for reading!

Hi,

I assume you have carefully read the introduction of the project writeup, explored the bibliography links, and researched the backgraound questions posed. If not, then that is the place to start answering your questions. I acknowledge that the resources provided are only a weak start. Here is a fairly good survey of magnetic phenomena at a very general level, but with lots of links to dig deeper:

http://en.wikipedia.org/wiki/Magnetism

Other possibly useful links:

http://www.school-for-champions.com/sci ... erials.htm

http://books.google.com/books?id=MgCExa ... &q&f=false

http://www.magnet.fsu.edu/education/tut ... index.html

http://sciencedemonstrations.fas.harvar ... depth.html

http://www.pha.jhu.edu/dept/lecdemo/EM-g3b.html

http://www.pha.jhu.edu/dept/lecdemo/EM-g3c.html

I hope these resources give you a better feel for what is going on in the interaction between metal objects in the presence of strong magnetic fields. Good luck!

Best regards,

Barrett L. Tomlinson

Thanks! The links helped me out a lot for my understanding of magnetism!
However, I still question the point of the vertical highwire.
While playing around with my project, I noticed that I could make the washers move up and down without the wire already.
I'm still just very confused as to why the piece of hanger is such a large factor in this experiment.

I'm still just very confused as to why the piece of hanger is such a large factor in this experiment.

Your experimentation with steel washers (ferromagnetic material) suggests that the coat hanger isn't always a large factor.
If the coat hanger were plastic, then the only factor involved would be a mechanical stop so that the coins or washers would not wobble as much along their vertical axis as they move up and down. If the coat hanger was a mild steel (ferromagnetic material), then any coin or washer that is ferromagnetic will have some magnetic attractive force to the coat hanger in the presence of the strong magnet on the other side of the plexiglass. If the only materials you are using are steel washers, then you won't see how the hanger affects other kinds of materials, so I'm not surprised that you are puzzled by what affects it actually has.

Thanks so much Mr. Craig Bridge!
That made a ton of sense.
Also, Thank you Mr. BLT!

I really appreciate your guys' help especially since i'm a stranger (: