Built on Facts

Archives for March, 2010

A Brief History of Light

So what exactly is light, anyway? It’s a tough question. Isaac Newton thought it was composed of streams of microscopic particles he called corpuscles. Really it wasn’t a bad idea. Light rays travel in straight lines just like fast moving projectiles, light bounces off objects in a manner not entirely unlike a ricocheting bullet, and…

If you happen to be in the Bryan/College Station area tomorrow, you might consider checking out the Texas A&M Physics Festival. It’s sort of an open house with a ridiculous number of top-notch physics demonstrations as well as some very interesting talks. It’s free! I’ll be there helping out with some of the optics demos.…

Somehow – and I don’t know exactly how, you know how the internet is – I came across this odd but cute song by the ineffable Weird Al. It’s an almost seven-minute(!) ode to the roadside attraction that is the titular biggest ball of twine. The twine ball actually exists, and lives in Darwin, Minnesota.…

Sunday Function

This is the graph of the line y = x: If you put your finger down on any point on that line, and then put another finger on another point on that line, you find that the total change in the y-coordinate divided by the total change in the x-coordinate between those two positions is…

Death-Defying Inclined Planes!

GrrlScientist sends a link to this rather wild stunt from India: How is it possible? What kind of friction is necessary, and is it any more difficult for the cars to do the stunt than it is for the motorcycles? Before we do any math, I want to think about the problem qualitatively. Let’s tally…

Sunday Function

Sine, cosine, and tangent are of course the workhorse functions of trigonometry. You learn ‘em in high school, and if you go on in math and science you never stop using them. Now on many occasions you might have the sine or cosine or tangent of some angle, and you want a way to invert…

Stealth in Space, pt. 2

In the Stealth in Space post earlier this week, we discussed the problem of detecting the thermal emission from a spacecraft. If the interior isn’t generating a lot of power, there’s not much thermal radiation being emitted, making it a tough job to detect. But it was pointed out in the comments that the heat…

Stealth in Space

While doing some poking around online, I came across a website called Project Rho, which tries to provide some science background for science fiction writers who want some degree of technical accuracy in their imaginative work. Generally it looks like they’re on the right track. In their section on stealth in space, they explain with…

Sunday Function

This Sunday I was at an event that involved a number of drawings for door prizes. There were perhaps 30 couples there – it was, not to beat around the bush, a wedding registry shindig at Bed, Bath, & Beyond. (Did I mention I’m recently engaged? I am. It’s the main reason for the endemic…

If you read about science at all, you’ve heard of Heisenberg’s uncertainty principle. It’s the canonical example of quantum weirdness, the strange idea that you can’t simultaneously know the position and momentum of a particle. Pack a particle into a small enough box and your accurate knowledge of position will necessarily cause that particle to…