Sunday, October 10, 2010
Saturday, October 02, 2010
Monday, August 30, 2010
Tuesday, June 29, 2010
At the same time, over the last year and a half I've become a total Facebook addict. So despite the fact that I eventually found the "ShareThis" app that lets me post things easily to Blogger, I got into the habit of posting interesting links and opinions to my Facebook page instead of to my blog.
This has had some interesting consequences, including at times vehement comment-thread debates among friends with different perspectives. I posted oh, roughly half a million links about the healthcare debate, and several of my friends did as well. Since that vote took place, Facebook silence all around. We sort of burned out on it. Which, in the grand scheme of things, is probably good for all of us and our relationships.
I may or may not return to posting miscellany on this blog. My time constraints haven't changed, and the only reason I have time to post this is that I'm home sick. But for those of you who occasionally check in here, I wanted to alert you to the Facebook page for my musical project. I'll be updating that frequently as I enter the mixing/mastering stage.
Tuesday, October 27, 2009
The issue here is that "enormous" is an adjective, and in those all-too-frequent cases in which a noun is called for, lazy writers cheaply noun-ify the adjective. This practice is even odiouser than lazily adverbifying an adjective. (See what I mean?)
The problem is that "enormity" already has a well-established definition. An "enormity" is a monstrous injustice, a grave moral wickedness, an ugly sort of travesty. Think of it this way:
- Hurricane Katrina was enormous.
- The aftermath of Katrina was widely regarded as an enormity.
Be not deceived, dear reader: the definition matters. These two possible choices of definition for "enormity" are nearly impossible to differentiate based on context alone. Consider the following: "She was stunned by the sheer enormity of the thing." Two quite different meanings arise, do they not?
(For the inevitable exception to the rule, I suggest the following: The healthcailoutulus bill was an enormity. Works on multiple levels, that.)
Saturday, October 17, 2009
Unless you've been hiding under a rock for the past few days, you heard about the reality-TV-"star" family drama this week in which 6-year-old Falcon Heene was alleged by his 9-year-old brother to have flown away in a homemade helium balloon. (Yes, his name was Falcon; you can't make this stuff up. Well, I couldn't, anyway - I won't speak for you.) The story exploded when the balloon finally fell to earth and rescuers found no one inside. After a long search, the boy was found hiding in the attic over the family garage; he had never been in the balloon.
Reporters were admittedly unsure whether the boy was actually in the balloon as it rose to 7000 feet and drifted some 50 miles. It seems, however, that no one in most newsrooms or in the police department tried to actually figure out, scientifically, whether the boy could have been in the balloon at all and have it fly. Surely no blame should be placed on the police; they are obligated to act to prevent the worst-case scenario. That said, the calculation isn't terribly difficult, and is worth noting for future reference. In this case, the calculation doesn't give a definitive answer, at least not with the information some physicist on the other side of the country reading a sketchy AP article has access to. But we can draw a few conclusions.
Here's how to determine whether the balloon could lift the boy. There are two forces at work in the problem: 1) gravity pulling down, and 2) the buoyant force of the atmosphere pushing up the less dense helium-filled balloon. It's really this simple; if the gravitational weight force of the boy + balloon is greater than the buoyant force, he won't get off the ground. If the buoyant force is bigger, he flies. Here's what you need to know for the calculation:
- The weight of the boy: A typical 6-year-old probably weighs 50 pounds. For calculations, it's more convenient to use metric (SI) units, which in this case means that the boy's mass is 22.5 kg (kilograms) and the gravitational force on the boy is 222 N (Newtons).
- The weight of the balloon: This is something we don't know, but can estimate. The balloon's weight comes from the Mylar and the carriage. We'll come to this again in a few minutes.
- The volume of helium in the balloon: We know this because we know that the balloon was "saucer-shaped", about 20 feet wide and 5 feet tall. A saucer shape is mathematically approximated by an "oblate ellipsoid", which is just a squashed sphere. The formula for the volume of an oblate ellipsoid is V = 4/3 * pi * a^2 *b, where a and b are the half-width along the long and short dimensions respectively. Here a = 10 ft and b = 2.5 ft. Plugging in these numbers, we compute a volume of 880 cubic feet of helium. In metric units, that's 24.9 cubic meters.
- The densities of helium and air: We know this from the Internet, or from a chemistry textbook. The density of helium is about 0.18 kg/m^3, and the density of air is about 1.25 kg/m^3. Helium is much less dense than air; that's why it floats - or really, why the air sinks around it. (Interestingly, the buoyant force is just gravity in disguise.)
We already know that the weight-force of the boy is about 222 N. With just the weight of the boy accounted for, there would be about 40 N of lift force left over in this equation, because 261 N - 222 N = 39 N. To translate back into English units, that's just about 9 pounds.
That means that if the Mylar balloon and whatever carriage or box the boy would have been sitting in weighed only ten pounds, the boy would not leave the ground.
Keep in mind a couple of things: First, if you saw the balloon on the TV, it looked like the balloon wasn't quite fully inflated. This was probably because it had a small leak that allowed helium to escape so the balloon could descend. However, if the balloon had been filled only to 80% of capacity, it definitely could not have taken off with the boy on board. (Tip o' the cap to a chemistry professor friend of mine who commented on Facebook!)
Second, let's assume for the sake of argument that the balloon was full and the box and balloon weighed only five pounds, leaving 4 pounds of lift force (or in SI units, 18 Newtons). We can calculate how fast the boy would have left the ground, again using the equation F = ma. In this case, we know the force (18 N) and the mass (24.9 kg), and we want to know the upward acceleration of the balloon. Rearranging the equation to read a = F/m, we compute a = 0.72 m/s^2.
That means that the boy's speed would increase by 0.72 meters per second every second. So after one second, his upward speed would be 0.72 m/s, which is 1.6 miles per hour - a pretty gentle start. After two seconds, he would be a few feet off the ground and his speed would be 3.2 miles per hour. But after ten seconds, assuming he didn't jump off after two seconds when he realized what was happening, he would be a couple of stories up and going at the healthy rate of 16 miles per hour. (Now, admittedly, we've assumed that the balloon box was overly light in this analysis - but the point is, it doesn't take much of a difference between the boy+balloon weight and the buoyant force to send someone traveling up pretty quickly.)
So to sum up, it's not terribly likely that the boy would be able to float away with that balloon - but it's just close enough to give a police chief heartburn, even if he had done the calculation, in this case.
One of the reasons why people are inclined to believe that anyone could float away in a balloon is the famous case of Lawn Chair Larry, winner of an Honorable Mention in the Darwin Awards. In 1982, Larry Walters strapped a bunch of weather balloons to his lawn chair and, miscalculating, ended up floating to 16,000 feet and trespassing on LAX Airport airspace! You can read all about it at the links. What I want to point out is that the Darwin Awards write-up is particularly interesting in light of the above calculation - because if you believe what they have to say about the balloons, Larry never would have gotten off the ground.
The Darwin Awards story says that the 45 weather balloons Larry strapped to his chair were 4-foot-diameter balloons. They even calculated for you how many cubic feet of helium one of the balloons contains (33). Here's the problem: If you go through the math, 45 x 33 is 1485 cubic feet, or 42 cubic meters. The buoyant force from 42 cubic meters of helium is 440 N, which in English is 99 pounds. Judging from the picture, Larry was not anorexic. Between him and his chair and his cooler, there had to be at least 200 pounds. There's no way he ever would have left the ground if he had been using 4 foot balloons, much less "taken off like a shot", as the writeup claims.
Here's the mistake: Look at the picture of the chair and the balloons: the balloons were considerably larger than Larry in his chair. This Wired article corrects the record - there were 42 balloons and they were eight feet in diameter. Okay, wrong by a factor of two, no big deal, you say? Wrong! A factor of two in diameter means a factor of eight in volume, and therefore the buoyant force (subtracting 3 balloons) was 740 pounds! Let's calculate the upward acceleration like we did for the boy, assuming Larry + chair weighed 200 pounds: a = F/m = 2402 N / 90 kg = 26.7 m/s^2.
By comparison, the acceleration due to gravity is 9.8 m/s^2, sometimes referred to as 1 "G". So when Larry's friends cut the ropes, he was pulling almost 3 Gs. The Darwin Awards article says "he streaked into the LA sky as if shot from a cannon"; indeed!
HowStuffWorks has a nice synopsis of helium balloons, too.
UPDATE 10/18: The balloon story is now believed to have been an intentional hoax. One of the reasons that police arrive at this conclusion (aside from the boy's inadvertent confession on Larry King Live) is that, while Falcon weighed only 37 pounds (!), the balloon weighed 18 pounds more than what the publicity-hound Heene dad originally told police. After more precisely measuring how big the balloon is, investigators have concluded that Falcon never could have gotten off the ground after all. Physics 1, Reality TV 0!
Friday, October 09, 2009
There's only one possible explanation for this that I can see:
The Nobel Peace Prize must now be the booby prize for missing out on the Olympics.
Okay, okay, seriously: President Obama got the award for not being G. W. Bush. Don't laugh - even the AP thinks so. Check the article:
The award appeared to be a slap at Bush from a committee that harshly criticized Obama's predecessor for his largely unilateral military action in the wake of the Sept. 11 terror attacks. The Nobel committee praised Obama's creation of "a new climate in international politics" and said he had returned multilateral diplomacy and institutions like the U.N. to the center of the world stage.Given that, how upset must Hillary Clinton be right about now for losing the nomination?? I wouldn't want to be within 50 miles of D.C. this morning.
(uh, wait. Er...)
And oh-by-the-way, as SNL helpfully noted:
- We're still in Iraq.
- We still haven't figured out Afghanistan.
- Gitmo hasn't been closed.
The Prime Minister's quote is almost beyond satire:
"The exciting and important thing about this prize is that it's given to someone ... who has the power to contribute to peace,"Come again? Here's the actual requirement courtesy of said. Nobelprize.org:
"the person who shall have done the most or the best work for fraternity between nations, for the abolition or reduction of standing armies and for the holding and promotion of peace congresses"Emphasis mine. See the SNL skit above. Was there nobody else they could have awarded this to? In fact, they've actually not awarded anyone the Prize on 19 different occasions!
Obama hasn't done anything, except give a few international speeches mostly apologizing for America. The Norwegian parliamentary committee failed to follow their own guidelines in handing out this award.
Monday, October 05, 2009
And so it begins.
I've now seen this mistake twice today: once in a job posting and once in an opinion article. Here we go:
A "tenant" is someone who occupies a dwelling; the usual usage refers to someone who is renting it from a landlord.
A "tenet" is a doctrine, belief, or principle. (That's principle, not principal. I'm not going over that again; you should have learned it the first time.)
To say you wish to hire someone who is "familiar with the tenants of physics and engineering" is to say that you want someone who has merely met the faculty at a research university. In that case, you have first forgotten to capitalize Physics and Engineering as the title of the building, and, secondly, you may have caused consternation among some of the non-tenured faculty by drawing attention to their less-than-permanent employment status.
You may not sleep better knowing this, but you should.
The particular mistake occurs here, painfully, just before the end of the first page, in an otherwise well-reasoned article - the first I've seen by a liberal publication acknowledging the legality in principle of the present Honduran administration and questioning the Obama administration's position.
That's all for now - sweet dreams.
Thursday, May 07, 2009
As I said, I'm glad that Carrie stood on principle. I don't think she was treated fairly. I am not surprised, but I am disappointed that she has been so abused for stating her opinion. Up to this point I'm with you. But when we begin to see a beauty queen as our best spokesman on the topic of same-sex unions, I have a problem. Congratulations, Carrie, for standing on the truth. Now, can we find a better "front man"?Yes, please. And don't miss Stan's followup post, either:
One side says, "We are intolerant and judgmental of sin" and the other side says "We are not intolerant or judgmental ... but we hate everything you believe". Which of those is hypocritical? You tell me.
Sunday, April 26, 2009
Thursday, April 23, 2009
The worst inclusion is the one I read most recently: The Catcher in the Rye. The only reason I finally picked it up last year, to be honest, was that I felt a little like Mel Gibson's character in Conspiracy Theory: it was a classic that everyone had read, except me. I suppose I wanted to feel "normal".
Guess what? Normal sucks. Catcher is a lame excuse to force (or, alternately, allow) high-schoolers to read the F-bomb approximately one thousand times in one hundred pages.
So here are the other ones that I've read: The Bible (duh); Declaration of Independence/Constitution/Gettysburg); Huck Finn (though I preferred Tom Sawyer); Macbeth; The Iliad; Great Expectations; 1984; The Scarlet Letter; Chaucer's Canterbury Tales; Frost's poems; Dickinson's poems; and Machiavelli's Prince. Those are the ones I remember, anyway, and without exception I'd recommend them. I'm still partial to John Wesley's quote regarding The Prince (tip o' the cap to this blogger, who perhaps has been raised on the A Beka Book curriculum, as I was):
“In my passage home [from Scotland], having procured a celebrated book, (the Works of Nicholas Machiavel,) I set myself carefully to read and consider it. I began with a prejudice in his favour, having been informed, he had often been misunderstood, and greatly misrepresented. I weighed the sentiments that were less common; transcribed the passages wherein they were contained; compared one passage with another, and endeavoured to form a cool, impartial judgment. And my cool judgment is, that if all the other doctrines of devils which have been committed to writing since letters were in the world were collected together in one volume, it would fall short of this; and, that should a Prince form himself by this book, so calmly recommending hypocrisy, treachery, lying, robbery, oppression, adultery, whoredom, and murder of all kinds, Domitian or Nero would be an angel of light, compared to that man.”UPDATE: Jeff the Baptist linked - thanks!
Sunday, April 19, 2009
I don't doubt that having certain levels of certain chemicals in wastewater streams is a bad thing. But stories like this (linked by Instapundit) do not prove that those levels exist. (To his credit, Prof. Reynolds says so, too.) Furthermore, the numbers they do present occasionally undermine their narrative. Consider the following:
Two common industrial chemicals that are also pharmaceuticals - the antiseptics phenol and hydrogen peroxide - account for 92 percent of the 271 million pounds identified as coming from drugmakers and other manufacturers. Both can be toxic and both are considered to be ubiquitous in the environment.Wait a minute - 92% of the load that you're wigging out about consists of antiseptics? And they're ubiquitous in the environment anyway? Color me unimpressed. Two paragraphs later there's this:
Residues are often released into the environment when manufacturing equipment is cleaned.I suppose they'd rather we leave the toxic stuff in concentrated form on the factory equipment for the workers to get sick on. More:
What's more, because the EPA hasn't concluded at what level, if any, pharmaceuticals are bad for the environment or harmful to people, drugmakers almost never have to report the release of pharmaceuticals they produce.Since we don't really know what level is harmful to people, and given the dramatic and proven benefits that pharmaceuticals have generally been to human populations, shouldn't the burden of proof be on these advocacy organizations to demonstrate that a given level is toxic?
Another codeine plant, run by Johnson & Johnson subsidiary Noramco Inc., is about seven miles away. A Noramco spokesman acknowledged that the Wilmington, Del., factory had voluntarily tested its wastewater and found codeine in trace concentrations thousands of times greater than what was found in the Delaware River. "The amounts of codeine we measured in the wastewater, prior to releasing it to the City of Wilmington, are not considered to be hazardous to the environment," said a company spokesman.Classic alarmism. They don't tell us what the absolute levels are in the Delaware River or in the waste stream, or compare those to any known standard or toxicity level. They just insert the entirely plausible statement that the level in the wastewater is THOUSANDS OF TIMES GREATER than the general level, insinuating that THIS IS BAD without ever establishing that as a fact. If you'll pardon the imagery, this is a little bit like complaining that the level of poop in my sewage pipe is THOUSANDS OF TIMES GREATER than the level in the Atlantic Ocean. It may be true, but it's entirely irrelevant.
I'm all for avoiding obvious mistakes by dumping drugs into rivers at concentrations that are known to be harmful to humans, even locally. But I want to see some hard numbers, like, say, the number of gallons of water these 271 million pounds of toxic substances were dumped into, before I'm convinced.
Wednesday, April 08, 2009
Ladies and gentlemen, allow me to present two engineering feats for the ages:
The above technology is based on an older version, seen here:
I can't wait for the 21st century edition. I think there's some serious stimulus opportunities with this technology...
Monday, April 06, 2009
Finally, an idea that could benefit both Detroit and everyday Americans. We're talking about a cash-for-clunker idea that needs fine tuning but should see fast action in Congress.Um, can somebody explain to me how a $5000 government rebate for trading in your 2006 Hummer fails to qualify as "another Washington handout"?
The plan calls for government rebates ranging from $3,000 to $5,000 for drivers who turn in older, low-mileage gas hogs. The payments could be used to buy gas-thrifty, newer models, providing an instant boost to automakers.
It's an across-the-board win: Gas guzzling clunkers will be retired, more efficient cars and trucks will take over, and pollution and foreign oil dependency lessened. Detroit stands to collect cash for its assembly-line output instead of begging for another Washington handout.