Physics Challenge Update

Marty McFly realizes he is running out
of time to submit his solution

Did you know that our Physics Challenge problem contest thingy is still up and going?  It is!  The contest will be open until the end of the day this Friday, November 4th.  And, unlike last time, the winning solution will be chosen and posted by the end of the weekend.  So even if you don't submit your own solution (though you totally should), check back here Monday morning for the winning entry.

Why should you submit a solution to our problem?  Lots of reasons!  The top ten reasons as decided by a random sample of me are given below the break.

The Linear Theory of Battleship

Recently I set out to hold a Battleship programming tournament here among some of the undergraduates. Naturally, I myself wanted to win. So, I got to thinking about the game, and developed what I like to call "the linear theory of battleship".

A demonstration of the fruits of my efforts can be found here. Below, my aim is to guide you through how I developed this theory, as an exercise in using physics to solve an interesting unknown problem.

Physics Challenge II: Marty McPhysics

Doc Brown didn't have a time-travel backup plan.

In light of the incredible success of our last Physics Challenge Problem (we received several responses), we here at the Virtuosi have decided to reinstate what was nominally a "monthly" contest. In addition to a brand-spankin'-new problem (with "prizes", see [1]), we have also tried to make a nice collaborative environment for discussing interesting physics problems and posting your own solutions. So I will discuss our new problem and then I'll throw it over to Alemi to discuss the goal of our new Physics Challenge webpage.

A Tweet is Worth (at least) 140 Words

So, I recently read An Introduction to Information Theory: Symbols, Signals and Noise.

It is a very nice popular introduction to Information Theory, a modern scientific pursuit to quantify information started by Claude Shannon in 1948.

This got me thinking. Increasingly, people try to hold conversations on Twitter, where posts are limited to 140 characters. Just how much information could you convey in 140 characters?

After some coding and investigation, I created this, an experimental twitter English compression algorithm capable of compressing around 140 words into 140 characters.

So, what's the story? Warning: It's a bit of a story, the juicy bits are at the end.

UPDATE: Tomo in the comments below made a chrome extension for the algorithm

Futurama Physics

The rotting corpses of sunbeams cause global warming.

Good news, everyone!  While rummaging through all my old stuff at home, I found my long-lost copy of Toto IV.  Huzzah for me!  This is entirely unrelated to what I wanted to talk about, but I have it on good authority that Toto's Africa syncs up really well with this post [1].  I'll tell you when to press play.

Anyway, what I really wanted to talk about was a fairly well-posed problem in Futurama.  In the episode "Crimes of the Hot," all of the Earth's robots vent their various "exhausts" into the sky at the same time, using the thrust to push the Earth into an orbit slightly further away from the sun.  As a result of this new orbit, the year is made longer by "exactly one week."  Anything that quantitative is pretty much asking to be analyzed.  Let's explore this problem a bit more then, why not?

Fun with an iPhone Accelerometer

The iPhone 3GS has a built-in accelerometer, the LIS302DL, which is primarily used for detecting device orientation. I wanted to come up with something interesting to do with it, but first I had to see how it did on some basic tests. It turns out that the tests gave really interesting results themselves! A drop test gave clean results and a spring test gave fantastic data; however a pendulum test gave some problems.

Physics in Sports: The Fosbury Flop

Physics has greatly influenced the progress of most sports. There have been continual improvements in equipment for safety or performance as well as improvements in technique. I'd like to talk about some physics in sports over a series of posts. Here I'll talk about a technique improvement in High Jumping, the Fosbury Flop.

Grains of Sand

Have you ever sat on a beach and wondered how many grains of sand there were?  I have, but I may be a special case.  Today we're going to take that a step further, and figure out how many grains of sand there are on the entire earth.  (Caveat: I'm only going to consider sand above the water level, since I don't have any idea what the composition of the ocean floor is).

Lifetime of Liquid Water

Apologies for the hiatus recently, it's been a busy time (when isn't it).  I hope to get back to talking about experiments soon, but for now I wanted to write up a quick problem I thought up a while back.  The question is this: how long does a molecule of H2O on earth remain in the liquid state, on average?

Coriolis Effect on a Home Run

Citizen's Bank Park

I like baseball.  Well, technically, I like laying[3] lying on the couch for three hours half-awake eating potato chips and mumbling obscenities at the television.  But let's not split hairs here.

Anyway, out of curiosity and in partial atonement for the sins of my past [1] I would now like to do a quick calculation to see how much effect the Coriolis force has on a home-run ball.