I always get a warm, fuzzy feeling when Google recognizes physicists in their Google doodle.
Today is Hans Christian Oersted’s birthday, and this famous physicist has been shown the love:
.
Danish natural philosopher Oersted was one of the first physicists to link electricity and magnetism. His work paved the way for James Clerk Maxwell’s revolutionary four equations that perfectly mathematically-modeled electromagnetism.
As a physics undergraduate, I never opted to take a circuit theory class. That never bothered me when I was a student. But now, as an adult, seeing the Maker movement in full swing, I’m kicking myself that I never got into electronics.
My dear wife got me a soldering iron, an Arduino Duemilanove, and lots of miscellaneous electronics-related supplies last Christmas, to help me fill this gap in my education.
And finally, last night I sat down and in two hours completed my first soldering project: the Adafruit Industries TV-B-Gone v1.1.
The TV-B-Gone is a simple device whose sole job is to turn off television sets. That might not be too useful at home, since you already have a remote for that. But, consider being out at a bar or restaurant or waiting room, trying to talk to friends or read in peace, while the incessant chatter of talking heads drills its way into your skull. (Why no, I’ve never experienced this, why do you ask?) The TV-B-Gone is a godsend.
The TV-B-Gone kit contains four infrared LEDs, driven by a microcontroller that contains the codes for all major brands of television sets. When you press the button, the TV-B-Gone flashes about 50 power-on codes in sequence, one after another. One of them should turn off the television, giving you the peace you deserve.
(Since televisions use the same codes to turn off and turn on a television, the same TV-B-Gone can be used to atone for your crime if you get caught.)
I opened up the kit and went through the parts list, as recommended. All the parts were included (a very important first step). I brought up the soldering instructions and got to work.
After about two hours of work I was finished, and ready to test my creation. I pointed the infrared LEDs into my phone’s camera, and I could see them flicker when I pressed the button. (Digital cameras can see infrared.) Success!
I liked this kit. The instructions were exceptionally clear, with plenty of photos. The printed circuit board was very clearly marked — if you’re soldering this kit, you have to really have your head in the clouds to mount a component in the wrong place. (And if your mind isn’t on your work, should you really be wielding a 700°F metal stick? Didn’t think so.)
The instructions also provided an intermediate step for testing the device half-way through the build. I understand this isn’t possible for some projects, but I liked having a point at which I could stop, take a break, and verify that what I was doing was working.
I have one very tiny complaint; I would have liked a little more of an explanation of why certain components are needed in the circuit. But I understand that this is a kit for beginners, and too much information might prove confusing.
I heartily recommend the Adafruit electronics kits. I’ll be buying one or two more kits for soldering practice before I start working on my own projects. I think I’ll try the Drawdio next, then perhaps the Conway’s Game of Life kit. If you want to buy the TV-B-Gone kit I’ve mentioned, go here.
Hats off to Ladyada (Limor Fried) for creating a fantastic product.
And, dear readers, if I come over to your house and the television spontaneously turns off? It wasn’t me.
Quick! Before it goes away! On the front page of CNN:
Jupiter’s stormy Great Red Spot is shrinking
I feel that I’m constantly harping on bad science, so it’s only fair that I recognize good science journalism too. Way to go, A. Pawlowski! Excellent article. (And sorry that your name ended up in eight-point type, barely visible in the byline.)
Why is this good science journalism?
The tone is rational. The author of the article accurately portrayed the shrinking of the Great Red Spot as a natural phenomenon. At no point does Pawlowski even hint that “ZOMG Jupiter’s going to explode!” or any similar outlandish claims that media sensationalism seems to demand.
The author compared the phenomenon to concepts familiar to lay readers. Pawlowski compares the Spot to hurricanes, a very appropriate analogy, and one that most readers can comprehend. Analogies in science are exceptionally important, as they allow us to incorporate new knowledge into what we already have learned through experience.
Reasonable scale is given for laypeople to determine the magnitude of a quantity. In this case, the rate of the Spot’s size change. By providing anecdotal “measurements” of the Spot’s size over the past hundred years, Pawlowski allows us to envision what Jupiter has looked like through history.
The author assumed that the audience has an interest in the material. Where newspapers have gone wrong is trying to dumb down their general articles to appeal to everyone. News has become so ubiquitous that most readers (especially on the Internet) only read items they have interest in. Chances are, if you’re reading a science article on CNN, you have at least a passing interest in science. That enables Pawlowski to go deeper into the science without fear of abandoning casual readers.
As a corollary, the author treats the reader with dignity. Pawlowski knows that the article’s readers aren’t idiots. So Pawlowski doesn’t mention that Jupiter is the fifth planet from the Sun, or that it’s a billion miles away. No one likes to be pandered to — so the author doesn’t even try. With the easy availability of Wikipedia, a reader that forgets the order of the planets can look it up quickly.
Way to go, CNN! Keep it up. And A. Pawlowski, if you’re ever in upstate New York, let me know. I’d like to buy you a beer.
Over on /., there’s an article on the front page discussing whether or not pre-med students should have to take organic chemistry.
I’ll talk about my opinion on this another time. The purpose of this post is to pass along a joke by commenter oskay:
A college physics professor was explaining a concept to his class when a pre-med student interrupted him.
“Why do we have to learn this stuff?” the student blurted out.
“To save lives,” the professor responded before continuing the lecture.
A few minutes later the student spoke up again. “Wait — how does physics save lives?”
The professor responded. “By keeping idiots out of medical school.”
Before Dragon*Con last week, Robin and I spent an evening with our old friends Bill and Jenn. What evening between friends would be complete without the consumption of adult beverages? In particular, Jenn’s deadly and delicious blueberry martinis?
Being the nerdy physicist that I’ve always been, I took my martini glass in hand and thought. Why are these particular glasses this odd shape?
The Wikipedia page on glassware gives a good overview of the different types of glasses. Until I started appreciating alcoholic beverages (over the age of 21, of course), I never realized exactly how many different types of glassware there are. It seems that just about every class of beverages has its own associated glass container. Even beer drinkers are particular about what they drink out of a pint glass, pilsner glass, bottle, or (sigh) can.
To put it terribly analytically, a glass is a potential well. When you pour a liquid into a glass and it comes to rest, the molecules don’t have enough total energy to make it out of the bowl of the glass. They stay there until they get enough energy to leave, or the walls around them disappear. This happens by one of three mechanisms.
First, you could make a pressure differential between the ambient air pressure and a region of the surface of the liquid. Because of the lower air pressure below your lips, atmospheric pressure pushing down on the rest of the liquid’s surface causes the liquid to ascend upwards in the region with lower pressure. Complex? Not really — you probably do this either by slurping or by using a straw.
Second, the random motion of a single molecule’s neighbors could happen to give the molecule enough energy to break through the intermolecular forces holding the molecule in the liquid. You can’t really plan this; it’s called “evaporation” and it just happens. Since you can’t actually productively imbibe any of the evaporated liquid anyway, this doesn’t really count.
Finally, and probably most frequently, you tip the glass (intentionally, sipping; unintentionally, spilling) to produce a spot in the near the liquid’s surface where the wall containing the liquid effectively disappears. Now that the liquid can be free, it is. Molecules nearest the gap in the wall fall out of the glass, hopefully into a waiting mouth below. Voilà, you’ve now tasted blueberry martini.
(Quantum wine in a potential well might leak out of the sides of the glass due to the process called quantum tunneling. Classical wine has no such problem. More on that some other time.)
So that’s why glassware works in the first place. But why do different glasses look so different when their purpose is the same?
Their purpose is not the same.
Some beverages are designed to stay at a constant temperature for as long as possible. Martinis and wines are a great example. Once the beverage leaves the temperature-controlled environment in which it’s stored or made (a cocktail shaker for the martini, a sommelier’s cellar or refrigerator for wine), normal heat transfer sets in. This means that the beverage will slowly start to creep towards the ambient temperature of the room. Or worse, the temperature of the hand holding the glass. The proper hand position to hold a wine glass is actually something like this:
CC-licensed photo from deepwarren on Flickr; original here
Holding a wine glass with the hand wrapped around the bowl will transmit a great deal of heat into the wine, changing its flavor (for the worse).
The purpose of a brandy snifter, on the other hand, is designed to transmit as much heat from the hand as possible to the liquor inside. Notice that the hand completely cups the bottom of the bowl, heating the brandy and allowing the vapors of the beverage to be released.
Credit: Wikimedia foundation
Certainly there’s a great deal of history that has gone into the shapes of glassware. The history of glassblowing itself is much to blame — it’s tough to make functional, resilient pieces of glass.
At least you don’t have to understand why glasses are designed the way they are to appreciate a tasty adult beverage. Drink up!
