Copasetic Flow

As the third week of the short summer session for freshman electromagnetism opens, the minds of young professors everywhere run towards cool polarized light demonstrations.  In helping track some of these down, I remembered that there was an awesome experiment involving sodium chlorate in a book titled "Crystals and Crystal Growing" by Alan Holden, Phylis Morrison.  It turns out that sodium chlorate crystals pass polarized light at different angles depending on the wavelength of the light.  In short, if you place a sodium chlorate crystal between two Polaroid sheets, and then rotate one while keeping the other still, you will see the color of light passed though the crystal change, (picture1)[1]. Detail of the Experiment Since I don't have time to grow a crystal, I thought it should be easy enough to find a video of the experiment  on the internet.  So far, I've searched to no avail though.  So, here's the challenge... Can anyone provide a...

Happy Fathers Day everybody!!! In honor of Fathers' Day, here are a few physicists who had kids that went on to become scientists themselves.  I know there are far more examples than I've listed here.  Feel free to add your favorites to the comments below! William Fairbank and William Fairbank Jr. William Fairbank Sr. performed one of the first two experiments that verified the existence of quantized magnetic flux[6].  He was also one of the architects of the Gravity Probe B experiment.  His son, William Fairbank Jr. is a physicists at Colorado State University who works on the detection of single atoms via photon burst mass spectroscopy (PBMS)[7]. Another one of William Fairbank's sons, Richard Fairbank, founded Capital One Bank which provided the last bit of funding so that work on Gravity Probe B could be completed after NASA quit funding it in 2008. Sydney and Persis Drell Sydney Drell proposed the Drell-Yan hadron scattering process in 1970. ...

As just about anyone using iGoogle has probably heard, it's one of the dying Google products, and will go away on November 1st of this year, (2013).  A number of the Copasetic Flows ham Eadio apps were turned into iGadgets and I've received a few inquiries about their ultimate fate.  Don't worry!  The apps will live on as embeddable iFrames for as long as the site keeps making enough to cover the hosting costs at Google.  Google app engine was free once upon a time, but no more, so if you're wondering why apps that you can embed have ads on them... That's why, but I digress. OK, so, how do you get your embedable apps?  Look below for links to each of the embeddable apps and the html code you'll need to add it to your site.  Just add the ifrme code to any web site you have edit access to, (including your blog for example), and the app will appear. Technician Class Practice Exam html code:  <iframe src="http://copaseticflows.appspot.com/techtest"...

I've been reading up on the twin paradox for the last year or so.  This is the paradox where one twin flies away from another at relativistic speeds and when they get back, they find that they're younger than their sibling who stayed home.   It amounts to time travel into the future. Last night when I got too tired to do anything productive I made a histogram, (shown in picture 2 below), using Google Scholar data of the number of citations containing the phrase 'twin paradox' over the years.  The first reference I found to the twin paradox was in 1956.  Prior to that it seems to have gone by the moniker of "Clock Paradox".  As I perused through the references, (there were a total of 2,393 between 1956 and 2013 by the way), one caught my eye because it was published by the U.S. Naval Research Laboratory in 1959[3].  As I've mentioned before, their was a push for anti-gravity in the late '50s and early '60s[8]. The document turned out to be...

We're planning an outreach event with Google at the G+  STEM on Google+ Community  where scientists, engineers, and mathematicians will answer questions via video like "Why do the STEM fields matter to you?"  Keep an eye on the community as this ought to be pretty fun and interesting, and it should kick off next Monday.  For the fun of it  here's my answer. References: 1.  STEM on Google+ Community https://plus.google.com/communities/110555615319066448343

So, in physics graduate school, you have your quantum mechanics, and your EM, and your statistical mechanics, and classical mechanics, and so on, and all of this is very well and good.  And then, if you're very, very lucky, there's machine shop class and it's awesome!!!  Obstensibly, the class is to teach you to be a better communicator with machine shops, but you still get to learn how to use the tools!  You actually get to learn how to build scientific instruments.  It's not for everyone though.  Heisenberg for example almost didn't get his PhD because of issues with his experimental lab grades. Machine shop started for me today after missing the first two meetings for an engineering conference last week.  Today we started in with the tools.  If you'd told me last week that an hour long lecture on saws would be interesting, I might have rolled my eyes, but not anymore!  We learned about a few different kinds of saws.  Then, we learned t...

If a Lorentz contracted rod travels over a hole smaller than it's un-contracted length, does it fall in?  Wolfgang Rindler, (picture 1), pointed out the answer in 1961.  Dr. Rindler is my new favorite author for the week.  His papers are paragons of clarity.  Rather than immediately bogging down in formulas or complicated jargon, he spends a significant amount of space in every paper explaining the problem and its solution in everyday terms.  Then, almost as an afterthought, he lays out the math that describes the situation.  Sometimes though, you have to read into his math and then read in a little more.  If anyone has a more clear explanation of the rod and hole contradiction, it would be great to hear. Dr. Rindler has done interesting work on special relativity, general relativity, and cosmology.  He moved to the Southwest Center for Advanced Studies in the mid '60s, and he's still there.  The institute now bears a different name howev...