I've been reading books by and about awesome women this month!  One's set in modern times, the other is set at the beginning of the last century.  Both tell the tales of women who built extraordinary media empires.  One was born into privilege, the other into homeschooling in the South.  They both did things the way they wanted to!

You're Never Weird on the Internet (Almost)
What a fun book to read! I found out about Felicia Day first when my future wife told me about Dr. Horrible and later, on Eureka. This book details Day's experiences through the present day: what it was like to be home schooled, how she started started a successful internet company, and what it's like to be a fan icon. The stories are entertaining and funny even when they deal with serious subjects like depression and creative burnout.

I approached the book from a curious perspective. What does it take to be an internet sensation? This book was remarkably clear on just how much work it takes. It didn't shy away from descriptions of the massive amounts of effort expended by Day and others as some biographies/memoirs do. An awesome read with plenty of detail!

The Huntress: The Adventures, Escapades, and Triumphs of Alicia Patterson: Aviatrix, Sportswoman, Journalist, Publisher
Alicia Patterson founded Newsday. Before that, she was a wild game hunter, accomplished equestrienne, wild game hunter, and aviatrix. Born into privilege as the black sheep daughter of the family that owned the Chicago Tribune Ms. Patterson lived a life full of adventure and journalistic accomplishment. The book entertains while it educates by detailing the fascinating historical backdrop of Patterson's life.



### Cool Math Tricks: Deriving the Divergence, (Del or Nabla) into New (Cylindrical) Coordinate Systems

The following is a pretty lengthy procedure, but converting the divergence, (nabla, del) operator between coordinate systems comes up pretty often. While there are tables for converting between common coordinate systems, there seem to be fewer explanations of the procedure for deriving the conversion, so here goes!

What do we actually want?

To convert the Cartesian nabla

to the nabla for another coordinate system, say… cylindrical coordinates.

What we’ll need:

1. The Cartesian Nabla:

2. A set of equations relating the Cartesian coordinates to cylindrical coordinates:

3. A set of equations relating the Cartesian basis vectors to the basis vectors of the new coordinate system:

How to do it:

Use the chain rule for differentiation to convert the derivatives with respect to the Cartesian variables to derivatives with respect to the cylindrical variables.

The chain rule can be used to convert a differential operator in terms of one variable into a series of differential operators in terms of othe…

### Lab Book 2014_07_10 More NaI Characterization

Summary: Much more plunking around with the NaI detector and sources today.  A Pb shield was built to eliminate cosmic ray muons as well as potassium 40 radiation from the concreted building.  The spectra are much cleaner, but still don't have the count rates or distinctive peaks that are expected.
New to the experiment?  Scroll to the bottom to see background and get caught up.
Lab Book Threshold for the QVT is currently set at -1.49 volts.  Remember to divide this by 100 to get the actual threshold voltage. A new spectrum recording the lines of all three sources, Cs 137, Co 60, and Sr 90, was started at approximately 10:55. Took data for about an hour.
Started the Cs 137 only spectrum at about 11:55 AM

Here’s the no-source background from yesterday
In comparison, here’s the 3 source spectrum from this morning.

The three source spectrum shows peak structure not exhibited by the background alone. I forgot to take scope pictures of the Cs137 run. I do however, have the printout, and…

### Unschooling Math Jams: Squaring Numbers in their own Base

Some of the most fun I have working on math with seven year-old No. 1 is discovering new things about math myself.  Last week, we discovered that square of any number in its own base is 100!  Pretty cool!  As usual we figured it out by talking rather than by writing things down, and as usual it was sheer happenstance that we figured it out at all.  Here’s how it went.

I've really been looking forward to working through multiplication ala binary numbers with seven year-old No. 1.  She kind of beat me to the punch though: in the last few weeks she's been learning her multiplication tables in base 10 on her own.  This became apparent when five year-old No. 2 decided he wanted to do some 'schoolwork' a few days back.

"I can sing that song... about the letters? all by myself now!"  2 meant the alphabet song.  His attitude towards academics is the ultimate in not retaining unnecessary facts, not even the name of the song :)

After 2 had worked his way through the so…