Physics
rallain | March 25, 2009Tom and Jerry, or Fetch! with Ruff Ruffman?
Answer: Tom and Jerry.
What? Yes. The reason: Tom and Jerry has bad physics but does not pretend like it has good physics. I know this is probably going to "type-cast" me as "that guy that keeps attacking Ruff Ruffman." Soon to be followed by "Leave Ruff ALONE!" I am sorry, I can't help it. Here is my problem. If you are going be a show, do whatever you like (I might still make some comments). If you are going to be a show that attempts to teach some stuff, don't you think you should get it correct or at least not reinforce bad ideas?
The…
rallain | March 25, 2009Dan Meyer made this awesome photo. He posted it so that others could look at it and come up with lesson ideas to use with this. There are some very good suggestions in his comments. I wasn't going to analyze this because I didn't want to rob some students of the opportunity, but I can't resist. Also, I doubt the first step a student would use would be to google for the answer. HA! I just caught you, you googling student.
Ok - I will try not to post any data. However, I will post some info on how I analyzed this.
The photo is a composite image from a video clip of a person throwing a…
purepedantry | March 25, 2009I caught this interesting sentence over at Marginal Revolution:
as consumption approaches satiation, workers reduce their hours of work to prevent themselves from actually reaching satiation. More technically, as workers approach satiation, their labor supply curves start to "bend backwards." The result is that rising labor demand stemming from rising productivity raises wages yet reduces employment.
Reminds me of relativity. Thus, one would assume that satiation, like the speed of light, is a level of consumption that a workers can never reach.
I have no idea whether this comparison is…
drorzel | March 25, 2009I fell behind on course reports from my modern physics class a few weeks back, but I do mean to get back to them, when I have more time. The material remaining is the end-of-term sprint through a bunch of topics in modern physics-- three classes on atoms and molecules, three classes on solid state physics, three classes on nuclear and particle physics.
It's a mad dash through a lot of material (as the eventual course-wrap-up post will make clear), which raises one of the eternal questions of academia:
When teaching undergraduate students about a discipline, which is more important, breadth or…
drorzel | March 24, 2009Steve calls me out for not commenting on new stories about "cold fusion":
Becky and I have been having much more regular access to the internet since the power was fixed. We check e-mail just about everyday and can even skim yahoo news. Or Professor Orzel's blog. I heard on BBC radio yesterday that there are people who have claimed to have evidence of cold fusion - which made me immediately think of a physics graduate who worked on sonoluminescence (bubble fusion) and of a talk given at Union last year about bubble fusion. Which made me immediately think of Professor Orzel and his skepticism…
rallain | March 24, 2009There are some really cool questions out there. Questions that do not require a lot to ask and do not require a lot to answer. Here is one such question (I can't remember where I first found this question or something like it):
Suppose you put take two identical cans of soda out of the fridge and place them on the floor in the middle of a room. One can you leave alone and one can you cover with a wool blanket. After an hour, you come back and check on the two cans of soda. Which will be warmer?
First, why do I like this question? Mainly because everyone can give an answer. If asked…
drorzel | March 24, 2009One of the NCAA pools I'm in has a copy of Obama's bracket entered, and the last I checked, I'm a couple of games up on him. This means I'm as qualified as anyone else to offer a plan to fix the financial crisis, and I have just the plan we need.
On the question of the AIG bonuses, I'm pretty much in agreement with the people who say that it's not worth making too much fuss over less than a tenth of a percent of the total bailout funding they're received. Passing laws to punish specific individuals is a lousy precedent, and it's not worth corrupting our principles for such a pittance. Let the…
rallain | March 23, 2009I have always wanted to ask a question like this - but never found the right test for it. Perfect for a blog.
Question:
Suppose you are in your car at a stop light behind a truck. The truck is pulling a trailer with a rollable tractor on it.
When the light turns green, the truck starts to accelerate. However, the cable holding the tractor to the trailer breaks and the tractor starts to roll off the trailer. You are right behind the trailer. What do you do?
Do you have an answer yet? You should probably come up with one quickly. That tractor is rolling off now. I will put the answer…
sciencepunk | March 20, 2009
Gravity Pods isn't a new game, having hit the net back in 2007, but it's certainly worth a look if you haven't tried it before. The physics-based game runs on a simple premise: get your green rocket to the purple swirly thing. To do this you'll need to navigate the gravitational fields of numerous 'pods', which will pull your rocket off course. Of course, like the boffins at NASA / ESA you must learn to use these gravitational fields to slingshot your craft to its destination. There's a lot of trial and error involved, and your map is slowly painted in delightful swirly patterns showing…
drorzel | March 19, 2009I'm giving an exam this morning, then taking the afternoon off for my annual hoops overdose, so there won't be much physics commentary here for the next few days. If you want hot physics news, though, there are a bunch of bloggers at the March Meeting, providing summaries on the Internet:
Doug Natelson has two reports, plus scattered other commentary.
His Holiness is putting everything in one post
Ian Durham has a summary of the first couple of days
Andre at BioCurious has highlights of the biophysics talks
If I'm missing anything, leave a link in the comments.
drorzel | March 18, 2009Yesterday's bad graphic post spurred me to finally get around to doing the "Why Does Excel Suck So Much?" post I've been meaning to do for a while. I gripe about Excel a lot, as we're more or less forced to use it for data analysis in the intro labs (students who have taken the intro engineering course supposedly are taught how to work with Excel, and it's kind of difficult to buy a computer without it these days, so it eliminates the "I couldn't do anything with the data" excuse for not doing lab reports). This is a constant source of irritation, as the default settings are carefully chosen…
pontiff | March 18, 2009Things I learned at the APS March meeting. Updated as I learn them. That's right: real time updates of connectivity of my neurons translated into html translated into text and pictures on your browser.
A Yale experiment led by Robert Schoelkopf has demonstrated the Deutsch-Jozsa algorithm and Grover's algorithm (two qubit algorithms) using transmon qubits (superconducting qubits.) Fidelities for their implementation are in the 80 to 90 percent range. Paper: arXiv:0903.2030.
Also, congrats to Robert Schoelkopft for winning the "2009 Joseph F. Keithley Award For Advances in Measurement…
rallain | March 17, 2009Dear Ruff Ruffman,
My kids really like your show. However, there is a problem. You promote it like it is science, but the content keeps having mistakes in it. Previously, I pointed out your mistake about in infrared thermometer (if can't remember, you said the thermometer measures the temperature with a laser. In fact, the laser is just used to aim.)
So, you see, I don't just like to randomly attack people. The problem is that you are saying "hey look at science" but your science is wrong. I suggest you either a) stop pretending to be a science show or b) get a science advisor (I am…
drorzel | March 17, 2009I was busy with other stuff when this hit the blogs, but I did want to at least comment in passing on Fermilab's announcement that it still hasn't found the Higgs Boson. Detailed commentary is available from Tommaso Dorigo and John Conway.
If you're not a physicist, or even just not a particle physicist, it might seem a little surprising that "We still haven't found the Higgs" is worthy of a press release, let alone actual excitement. The important thing about the result is that they have been able to say (relatively) definitively that the Higgs boson does not exist in a certain range of…
pontiff | March 16, 2009Tonight I hop on a red-eye to Pittsburgh to attend the APS March meeting. 7000 physicists in Pittsburgh, now that's a scary thought for poor Pittsburgh (punishment for winning the superbowl, I guess.)
A list of highlighted papers includes some fun ones:
11:15AM, Tuesday Session B15: "Walking on water: why your feet get wet" Michael Shelley , Jake Fontana , Peter Palffy-Muhoray
1:15PM, Wednesday Session Q15: "Statistical laws for career longevity" Alexander Petersen , Woo-Sung Jung , Jae-Suk Yang , H. Eugene Stanley
rallain | March 16, 2009Better technology sometimes causes problems. In this case, technology has made video cameras really small. Small? That's a problem? Well, the problem (as I discussed previously) is that small cameras are not stable and make "shaky" videos. Well, then increase the mass of the camera - simple. I wanted to test this idea and make a test video with and without extra mass on the camera. I was thinking - what could I attach to it? A 2 lb or 5 lb scuba weight came to my mind. Then it hit me: a water bottle.
When do people use these little video cameras? To film their kids or something? If…
rallain | March 16, 2009I previously talked about measurements (some) when I looked at the uncertainty in the distance to the Sun. One of the simple ways of determining the uncertainty of a calculated quantity is to use the uncertainty of the measured variables and find the max and min that calculated quantity can be. The example I used was in calculating the uncertainty for the area of a rectangle. So, the maximum and min areas would be:
And then the uncertainty in the area can be described as:
Yes, I know this is not as sophisticated as the normal procedure for error propagation, but it works. This is the…
drorzel | March 16, 2009Scientific American has an article by David Albert and Rivka Galchen with the New Scientist-ish headline Was Einstein Wrong?: A Quantum Threat to Special Relativity and the sub-head "Entanglement, like many quantum effects, violates some of our deepest intuitions about the world. It may also undermine Einstein's special theory of relativity."
An alternate title for this post might be "Son Of Why I Won't Make It as a Philosopher," because I really don't know what to make of it. The authors make authoritative-sounding references to a bunch of papers I haven't read, but then they also drop in…
drorzel | March 16, 2009EurekAlert offered a press release from the American Physical Society over the weekend that may indicate that someone in the press office has won a round of drinks:
The American Physical Society (APS) is elated that the Senate has approved the FYO9 Omnibus Bill, which will allow scientists to continue cutting-edge research that will lead to innovation, job creation and economic growth for the United States.
"Elated" is not a word I expect to see in a press release. I suspect. Somebody in the press office may just have won a bet.
drorzel | March 14, 2009One of last year's highest-traffic posts was, weirdly, Talk Like a Physicist. I say "weirdly" because it wasn't much more than a link to Tom at Swans On Tea.
It's that time of year again, and Tom's back with an updated list of vocabulary for your physicist-talking needs. I don't have much to add, but one of Tom's items:
We physicists quantify relationships -- something that is complicated is "nonlinear," or even "highly nonlinear." Opposites are "inversely proportional"
reminded me of a great literary reference, from Ted Chiang's "Story of Your Life":
"So they can read a word with equal ease…