March 13th, 2007

Prof. Ned Brainard

Fun with Light

If you like physics and making stuff, you might want to look at this.

For the lazy:
I did a project in high school physics on the phenomenon of birefringence in combination with polarization. Take a clear sheet and a light source (we used transparencies and an overhead projector). Put loads of scotch tape haphazardly on the clear sheet (or, you know, the inside of your visor). When I say haphazardly, make sure it's good and flat but otherwise criss-cross it, make shapes, etc. If it's all going in one direction up and down, it's going to be boring. Put a polarizing filter between the sheet and the light source (or hold your scotch-taped visor up to the sun); we put thetransparency on top of a large polarizing filter sitting on the surface of the overhead projector. Then put another polarizing filter (your sunglasses, for example) between the transparency and the observer (your eyes or a projection screen) and rotate that polarizing filter. Congratulations, you've just created a Polarimandalascope.

Oh, and the trick is this: The tape is birefringent, thanks to the process of stretching by which it's made. In different layers, this alters the amount the light (which is already polarized) is bent. What you actually end up with is circular polarization, so that when you rotate the second polarizing filter, different frequencies (i.e., colors) of light have rotated different amounts and can therefore pass through. So what you see is a wide array of colors in all sorts of patterns, based on how the tape was applied.
  • Current Music
    Soul Coughing - $300
Wu-Tang Financial

Damn, it feels good to be a coder.

Those of you who are not stalking my every move might not know that I've decided to take up programming again. This afternoon on the train home, I wrote my first Python program:
# This program converts a number of minutes into hours.
m = input("How many minutes should I convert? ")
h = m / 60
print h
null = raw_input("Press ENTER to exit.")

Then I refined it:
# This program converts a number of minutes into hours,
# to two decimal places.

m = input("How many minutes should I convert? ")
h1 = m / 60
dec = (h1) * 60
# This variable compensates for python's inability to float.
h2 = 100 * (m - dec) / (60)
print h1,".",h2
null = raw_input("Press ENTER to exit.")

The final version will have to wait until I learn if-then statements, so that I can display the correct units (hour/s). I suppose I should probably comment that, since I'm more practicing comments than anything else.
# This program converts a number of minutes into hours and minutes

m = input("How many minutes should I convert? ")
h1 = m / 60
dec = (h1) * 60
h2 = m - dec
print h1,"hours, ",h2,"minutes."
null = raw_input("Press ENTER to exit.")

The text I'm teaching myself with is How to Think Like a Computer Scientist, for anyone who's curious.

Hopefully, all this effort will not detract from the time I'm devoting to penning my new sitcom: Chad Thuy, Pad Thai Guy. It's the story of the comic misadventures of a delivery guy who goes on to build an unstoppable empire of Pan-Asian Fast Food restaurants, which he rules with an iron fist. Or will, some day. That's not for a few seasons yet. I'm pitching it to the WB as a sort of Two Guys, a Girl, and a Pizza place meets Sopranos, but with yellow people. And never mind that according to America's one-drop rule I'm black; and not at all Asian, any way you slice it. I mean, Jews have been writing shows for black folks for decades now, right? *rimshot*
  • Current Music
    Rush - Grand Designs
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