Observations
  • Home
  • Observations
  • Trendcasting
  • Odds 'n Ends
  • Science/Technology/Experiments
  • Mental Health

The Barkhausen Effect...

7/31/2012

0 Comments

 
Picture
Video Below:
In the early 1900's, it was believed that ferromagnetic materials like iron, when placed in a coil of wire and subjected to a magnetic field, would orient the magnetic domains instantaneously. In 1919, Heinrich Barkhausen, while working in magnetism and acoustics, discovered that in fact, the orientation of the domains occurred in steps and in a discreet manner.
All ferromagnetic materials have domains that are, at the atomic level, are normally aligned in a straight line. When a magnetic field approaches, the domains align with the magnetic field.
This demonstration shows that effect and reproduces the results obtained by Barkhausen. If you need magnet wire to wind the coil for the experiment, Radio Shack has a three-pack of assorted gauges and lengths. But as you will see in the video, coil winding is not necessary. The links follow the video:


The first link is a MagLab discussion of the Barkhausen effect here. The second is an experiment with coil winding as I have done here. This link demonstrates the clicking sound better than I have but I am not sure why. Have fun with magnetism!
0 Comments

Percent Solids Determination and Homemade Weighing Cups

7/12/2012

0 Comments

 
Picture
Video Below:
Determining the percent solids in either a water based or organic solvent based material is a basic procedure used to make calculations for reactions, and in some cases, just curiosity. But, in the world of chemistry, it is a fundamental process. Although I used Elmer's glue as an example, all solutions and emulsions with solid constituents are applicable. The video is really self explanatory but here is the breakdown of the method:
  1. Weigh the aluminum cup. Label this A
  2. Without taring, add the wet sample. Label this B
  3. Let the sample evaporate or warm slowly to drive off the water or solvent. Label this C
  4. Weigh the now dry sample and the cup.
Now, use this simple formula to calculate the solid content:
C - A
B - A
Do the subtraction and divide the result and multiply by 100. You now have the amount of solid chemical in the cup in percent.  Enjoy!



0 Comments

    Author

    The author has an eclectic background in chemistry, electronics, writing, mental health, and community action...Ken

    Archives

    June 2021
    March 2020
    September 2019
    August 2018
    August 2017
    March 2017
    December 2016
    November 2016
    October 2016
    August 2016
    April 2016
    December 2015
    September 2015
    May 2015
    March 2015
    February 2015
    December 2014
    November 2014
    October 2014
    September 2014
    August 2014
    July 2014
    June 2014
    May 2014
    April 2014
    March 2014
    February 2014
    December 2013
    November 2013
    October 2013
    August 2013
    July 2013
    June 2013
    May 2013
    April 2013
    March 2013
    February 2013
    January 2013
    December 2012
    November 2012
    October 2012
    September 2012
    August 2012
    July 2012
    June 2012
    May 2012
    April 2012
    March 2012
    February 2012
    January 2012
    December 2011
    November 2011
    October 2011
    September 2011
    August 2011
    July 2011
    June 2011
    May 2011

    RSS Feed

    Categories

    All
    Acid And Bases
    Amateur Scientist
    Anodizing Aluminum
    Anthocyanin Indicator
    Ant Orientation
    Artificial Intelligence
    Bar And Cr Code
    Cable Tie
    Carbon Dioxide Fun
    Catalase And H2o2
    Chemical Art
    Cold Cathode
    Color Hot Glue Sticks
    Common Chemicals
    Copper Plating
    Cyanotype/Blueprint
    Dot Com
    Electroluminescence
    Epoxy Art
    Experiments
    Hydrogels
    Infrared Photography Basics
    Magnetic Money
    Old Textbooks
    Photograms
    Science
    Static Electricity Detector
    Technology
    Yogurt