What can a teacher do when the season’s cold, wet, or snowy weather makes curious and rambunctious children go stir crazy? This was exactly the predicament I found myself in with my five-year-old grandson last year. After sledding and playing in the snow, Henry and I looked for something else to do. I reached deep into my Nana brain and unlocked my inner teacher. “What’s your teachable moment today, Nana?” I murmured.
All weekend long, we had been experiencing the crackle and pop of static electricity as a result of the house’s warm, dry air. Henry himself had been zapped a half dozen times. Petting the family dog, he marveled as her hair stood on end. He was curious: what was this invisible power?
Ahhh, Eddy Current Tubes – you would never think that a hunk of copper pipe and a magnet could make anyone grin from ear to ear. I just love these things.
So simple in appearance, and yet so magical to see and use. Whenever I happen to have a set at home, I soon lose control of them to my wife who is just as fascinated by them as I am.
Although they can be used in fairly high end physics demonstrations, they are stunning enough that everyone who has a chance to see them is simply amazed.
Just realized – you may not have not seen one, have you? Here’s a video for you:
Kinda cool, huh? So, since I have (hopefully) gotten you to say “wow,” I’ll just bet you are wondering “why” — here’s some science:
Simple iron filings can be used for a variety of interesting experiments and demonstrations. Magnetism is a mysterious concept that can be difficult for students to grasp. Magnetic fields are the forces surrounding a magnet that are identified by how they interact with adjacent magnets and other metal objects. While magnetic fields are ‘invisible’ they can be observed by sprinkling iron filings on a white paper with magnets beneath.
We recognize heat & cold, dry & damp, light & dark, and sound & silence. However… I find it absolutely fascinating to consider that we also live withinsomething that we can’t see, hear, touch, or taste.
We all Know:
Our planet has a giant magnet near its core and that its field extends over the whole of the Earth’s surface. But, do we everreally think about this field that passes through soil, rocks, buildings… and us? Granted, relatively speaking this ‘field’ isn’t particularly strong. In fact, it’s a rather weak field when compared to those of a horseshoe magnet or, particularly, a modern Rare Earth magnet.
By Cathy Byrne
Posted by Donna Giachetti 
by Priscilla Robinson
All weekend long, we had been experiencing the crackle and pop of static electricity as a result of the house’s warm, dry air. Henry himself had been zapped a half dozen times. Petting the family dog, he marveled as her hair stood on end. He was curious: what was this invisible power?
by Ted Beyer
by: Martin Sagendorf