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Evolution and Science Education

No idea in science is as controversial as the theory of evolution. The controversy comes not from within science, but in that grey area where science and religion intersect. This is an issue I've been involved with for many years. Since my late teen years, in fact. I'm part of a group that administers the Talk.Origins Archive, which is probably the largest repository of information about the evolution vs creationism battle on the web. I'm also a founder and advisory board member of Michigan Citizens for Science and have worked closely with the National Center for Science Education for many…

Alvastra in the 1st Millennium

I really enjoyed my work yesterday. The forenoon saw me in the stores of the Museum of National Antiquities looking through Otto Frödin's uncatalogued finds from the "SverkersgÃ¥rden" site near Alvastra monastery. Not only did I find all the elusive 1st Millennium stuff that's mentioned in the literature but never illustrated, but I was also able to identify for the first time two small pieces of iron military equipment of the same date. These strengthen the case for counting SverkersgÃ¥rden among the province's rare Vendel Period elite settlements. After lunch at the Chinese place where I…

Natural Disasters and the "End Times"

The Worldnutdaily has this piece by Greg Laurie giving the usual "the end is near" screed that we hear after every major disaster. Laurie is a regular WND contributor and is the pastor of one of the largest churches in America, Harvest Christian Fellowship. So naturally, he can be relied upon to pass along a good bit of nonsense and false scientific claims to his followers while he's peddling his end-times theology: As we prepare to remember the horrific attack on American soil on 9-11, we may wonder could it be that all these things that are happening in our world today are actually signs of…

Bruce Springsteen and the E Street Band

Kate and I went to see Bruce Springsteen last night in Albany. The show was listed as starting at 7:30, but it was 8:25 before the band took the stage. At about 9:30, they were playing "Devil's Arcade," one of the slower and more political songs off the new record, which gave me time to look at my watch. "Huh," I said. "Must be getting near the end of the set." They finished "Devil's Arcade," and went into "The Rising." "Well," I thought while singing along, "This is a good song to end the set on." They finished, and went right into "Last to Die." "Bold call, ending on a track from the new…

Coffee as a source of biodiesel: A closer look

Owing to popular demand among the readership of this blog, I've taken a closer look at the original article claiming that spent coffee grounds can be employed as a source of fuel. There are several important details that come though in the paper coming out in the next issue of the Journal of Agricultural and Food Chemistry that have not come through in the press reports. From the paper: Figure 1. Schematic representation of the biodiesel production process from spent coffee grounds. The other value-added products such as H2, ethanol, and fuel pellets can also be achieved from this waste…

Horrific beetle sex - why the most successful males have the spikiest penises

If you've ever complained about having bad sex, you really have no idea. Human women may have to complain about poor stamina or incompetent technique but the female seed beetle (or bean weevil; Callosobruchus maculatus) has to contend with her partner's nightmarish penis - an organ covered in hard, sharp spikes. Just see if you can look at the picture on the right without wincing. It's no surprise then that females sustain heavy injuries during sex. But why have male beetles evolved such hellish genitals? What benefits do they gain by physically harming their partners? It's possible that…

Networks Under Construction

As biologists figure out more about how life is, they can then figure out how it got to be that way. First there were genes. Mendel noticed that somehow the wrinkles on wrinkled peas could be transmitted down through the generations, even if some of those generations had no wrinkles at all. It turned out that the wrinkles were the result of a gene; a different version of the gene produced smooth peas. For much of the twentieth century, evolutionary biologists worked out how changes in genes produced evolutionary change. A mutation that alters one position in a gene (or chops out a whole chunk…

Link between the Nuclear Export of mRNA and Decay

As many of you may know, I have been examining how mRNAs are transported and localized within the cell and how the regulation of mRNA metabolism contributes to gene expression. From data accumulated recently within the "RNA Field", we know that transcription in eukaryotic cells is very sloppy - that is, a plethora of different RNA transcripts are generated from seemingly random pieces of DNA. As I explained in a recent post, some of this background transcription seems to play a role in regulating how the DNA is packed and thus allows for a tighter control of RNA production from protein coding…

Blogger Challenge 2007: how's your team doing?

The 2007 DonorsChoose Blogger Challenge is in its last few days, which means there may be enough data to start identifying trends as to which ScienceBlogs readers are the most generous: By scientific discipline: Chad Orzel of Uncertain Principles is our lone full-time physical sciences blogger with a challenge this time around. He's more than halfway to his goal, but if you physics, astronomy, chemistry, and math types think you can do better vote with your donations and give Chad a boost. Two of the brain and behavior blogs that mounted challenges actually met them (Retrospectacle and Omni…

Slate's war on epidemiology continues

The editors at Slate really don't like epidemiology. Not content with Christopher Hitchens' clueless attack on the Lancet study they've published another attack on the study. And this one is by Fred Kaplan, the man who made such a dreadful hash of it when he tried to criticize the first Lancet study. Kaplan writes: The [first] study's sample was too small, the data-gathering too slipshod, the range of uncertainty so wide as to render the estimate useless. So he's learned nothing about statistics since his botched criticism of the first study. Kaplan concedes that the new study has a…

Finding Atlanta, Part 1

As you may have already guessed, things are beginning to normalize. We just finished moving in the rest of the furniture to our new place this past weekend, a cute little house in Midtown Atlanta. From our street you can see downtown, which is beautiful at night. Apparently, the previous owner's name was Hattie, who was a prominent member of one of the local Baptist churches (in the basement, our landlord found a plaque of some kind given to Hattie in honor of her service to the church). Hattie's old deep freeze, dryer and Frigidaire stove still work perfectly (and go perfectly with our…

Crude Comments

The latest news from the Gulf of Mexico offers both relief (the "top kill" approach to ending the oil spill may be working) and dismay (the amount of oil pouring into the water is now thought to be closer to 20,000 barrels a day rather than the 5,000 barrels that BP has insisted on for weeks.) In other words - at worst case - the U.S. Geological Survey estimates that the spill amount may be closer to 39 million gallons of oil so far, rather than the 11 million previously suspected. Now, I've spent the last week or so focusing on the chemical dispersants used to break down the oil,…

Extra Data Points on Gender and Science

Early last year when the whole Larry Summers saga broke out, I posted some data on gender and science that was floating in the public sphere. Here I've reposted some of this data. THEN I'll tell you some recent data from Harvard ... From a NY Times article Feb 22nd, 2005 Women in Physics Match Men in Success Dr. Ivie said the main reason fewer women made it to the top in physics was simply that fewer started at the bottom. At each job level, she said, the fraction of women matched what would be expected for women advancing at the same rate as men. And at top-tier universities, the…

A report from yesterday's protests

We've discussed yesterday's peaceful protest on behalf of Occupy Oakland, and the violent police response that dispersed that protest, but I want to quote at length from zunguzungu's excellent report: You might find it a bit confusing trying to keep track of the different times the Oakland Police department used tear gas on peaceful protesters yesterday. In the morning, they raided the Occupy Oakland camp and destroyed everything the occupiers had built, as I wrote about yesterday (and you can see video of that here). But then, in the afternoon, this march gathered at the Oakland public…

Comments of the Week #163: from the edge of the Universe to the Milky Way's demise

“Humanity has won its battle. Liberty now has a country.” -Marquis de Lafayette There's so much science to talk about in any given week here at Starts With A Bang! It's sometimes hard to choose, but one particular topic stole the show this past week: black holes. Sure, we took on other things, too, but we didn't even talk all that much about the biggest discovery of all: LIGO's direct detection of a third pair of merging black holes! If you had doubts after one, and they were allayed after two, then three should hammer home that these are real, robust and common. There are a lot of nuances to…

Comments of the Week #155: From Pure Energy To Earth's Twin

"You are not here merely to make a living. You are here in order to enable the world to live more amply, with greater vision, with a finer spirit of hope and achievement. You are here to enrich the world, and you impoverish yourself if you forget the errand." -Woodrow Wilson It's been another fantastic week here at Starts With A Bang, and I've got to laud all of you for doing your best to make it a good one! Let's get right into what this past week held: Is there any such thing as pure energy? (for Ask Ethan), More than stars: the Milky Way's dust mapped in 3D for the first time ever (for…

History, social science's nemesis?

A week ago I posted on the gender gap in politics; today Statistical Modeling, Causal Inference, and Social Science critiques a similar argument: Via Craig Newmark, I saw a column by John Lott summarizing his 1999 paper with Lawrence Kenny, "Did women's suffrage change the size and scope of government?" Lott and Kenny conclude Yes, by comparing the spending and revenue patterns of state governments before and after women were allowed to vote. I haven't looked at the analysis carefully and would need a little more convincing that it's not just a story of coinciding time trends (they have a…

A universal olfactory aesthetic?

Predicting Odor Pleasantness from Odorant Structure: Pleasantness as a Reflection of the Physical World: Although it is agreed that physicochemical features of molecules determine their perceived odor, the rules governing this relationship remain unknown. A significant obstacle to such understanding is the high dimensionality of features describing both percepts and molecules. We applied a statistical method to reduce dimensionality in both odor percepts and physicochemical descriptors for a large set of molecules. We found that the primary axis of perception was odor pleasantness, and…

Bloggingheads: Horgan and Johnson on Myers and MRI Mind-Reading

Today on ScienceBlogs.com, you will notice a new feature on the site. Instead of The Buzz, we have an embedded video from Bloggingheads.tv. This feature will appear every Saturday and can be viewed subsequently here on Page 3.14, the editorial blog of ScienceBlogs.com. This week, John Horgan from the Stevens Center for Science Writings and George Johnson, author of Fire in the Mind and The Ten Most Beautiful Experiments discuss recent attempts of scientists to use functional Magnetic Resonance Imaging technology to display graphic images on a computer screen directly from the visual cortex…

Medicine & Health Weekly Channel Highlights

In this post: the large version of the Medicine & Health channel photo, a comment from a reader, and the best posts of the week. A triathlete races to the finish in the IronMan Germany competition. From Flickr, by Novecentino Reader comment of the week: In Swallowing nutrition myths hook, line, and sinker, PalMD of denialism blog takes a New York Times article to task for its unfounded claims. The article lists 11 'super foods' which are claimed to have health benefits such as lowering cholesterol, controlling blood sugar, and fighting cancer among other things, but PalMD points out…

Pluto, King of the Underworlds

New measurements from NASA's New Horizons spacecraft revealed that Pluto, named for the Greco-Roman god once called Hades, is a little more swollen with ice than previously thought, making it the biggest trans-Neptunian object—more voluminous than rival dwarf planet Eris, which is nevertheless more massive. Greg Laden explains why these orbs are not considered full-fledged planets on his blog. While Eris orbits the Sun within the 'scattered disc,' Pluto orbits in the Kuiper Belt, a collection of gravelly snowballs that Ethan Siegel says outnumber all the planets in our galaxy. The Kuiper Belt…

Notes from a Parallel Universe, III: Moscow poultry producer branch

Here is another dispatch from our continuing series, Notes from a Parallel Universe (parts I and II here and here). In this universe there is a confirmed H5N1 outbreak near Moscow. In The Parallel Universe this is impossible: MOSCOW. Feb 18 (Interfax) - Experts from Rosptitsesoyuz, Russia's poultry producers association, say poultry farms in the Moscow region are immune to the bird flu virus. "All poultry farms in the Moscow region, and in the rest of Russia, have been working under a tight closed regime since August 2005, which rules out the spread of the bird flu virus to…

Pascal's birthday

From today's Quotes of the Day: Blaise Pascal was born at Clermont-Ferrand, in the Auvergne region of France, on this day in 1623. Educated at home by his father, he was a child prodigy and made significant contributions to the construction of mechanical calculators and the study of fluids. In mathematics he published a treatise on projection geometry (whatever that is!) at age sixteen and his work in probability theory is still important in economics today. In 1654 he had a vision upon awaking from a coma following a carriage accident, and devoted the rest of his life to philosophy and…

Justice meated [sic] out to serial (food) adulterer

Suppose you were a cattle dealer and the US Food and Drug Administration, one of the federal agencies tasked with keep the food supply safe issued you a court order, twice, prohibiting you from putting your product into the food supply until you complied with a legally required record keeping system. The agency had their eye on you because the meat you produced had been found repeatedly to have illegal levels of antibiotics making it unfit for human consumption. But you didn't care and you violated the court orders. So the FDA went after you and you were found in criminal and civil contempt…

Cyclone Sidr: Nature's waterboard

Our SciBlings at The Intersection, Chris Mooney and Sheril Kirshenbaum, remind us that pandemics aren't the only natural disaster. I'm kidding, of course. You knew there were others, right? Like Cyclone Sidr, practically on top of the people of Bangladesh. First story on CNN, right? I'm kidding of course. They have to wait for the bodies to wash up first. Anyway, Chris says the latest from the Joint Typhoon Warning Center (JTWC) has this hurricane bearing down on that poor country at almost Cat 5 levels and it may still be intensifying. Chris is the author of the excellent book, Storm…

How animals lose legs

What's with manatees in the news lately? First intelligence, and now this: Manatee Bones Lead To New Insight On Evolution: "Most research professors spend their days writing grants, teaching and managing graduate students, so when Stanford's David Kingsley, PhD, ventured from his office to his lab, pulled out a scale and started weighing 114 pairs of manatee pelvic bones, it was a sign that something was afoot. The results of Kingsley's efforts make his departure from the routine worthwhile. He found that in almost every case, the left pelvic bone outweighed the right. Although seemingly…

Friday Blog Roundup

Bloggers discuss food: Andrew Schneider at Secret Ingredients points out that FDA can't just shut down the facility responsible for salmonella-tainted peanut paste. Maryn McKenna has more bad news about the drug-resistant bacteria MRSA: now it's been found in Belgian chickens. Tom Philpott at Gristmill attends the Seafood Summit and makes analogies (between land- and sea-based food production, between marine and terrestrial monocultures, etc.). Andrew Revkin at Dot Earth reports on actions being taken to protect Arctic fish from overexploitation once more sea ice melts. Elsewhere: Jonathan…

US Postal Junk Mail Service

We're discussing a junk mail case from the 1970s in my information privacy law case. In Rowan, Justice Burger laments: ...the plethora of mass mailings subsidized by low postal rates, and the growth of the sale of large mailing lists as an industry, in itself, have changed the mailman from a carrier of primarily private communications, as he was in a more leisurely day, and have made him an adjunct of the mass mailer who sends unsolicited and often unwanted mail into every home. It places no strain on the doctrine of judicial notice to observe that, whether measured by pieces or pounds,…

Occupational Health News Roundup

Ground Zero workers are still in the news. Last week, a House Panel heard from Dr. Philip Landrigan of the Mount Sinai School of Medicine about the illnesses these workers suffer from. Earlier this week, several members of New York's Congressional delegation introduced the James Zadroga 9/11 Health and Compensation Act, which would would establish a long-term program to provide a broad range of physical and mental health services to Ground Zero workers. In other news: Charleston Gazette: According to new federal data, black lung disase rates in U.S. coal miners have doubled over the last…

New and Exciting in PLoS Biology

A nice integration over several levels of analysis: Adaptive Variation in Beach Mice Produced by Two Interacting Pigmentation Genes by Cynthia C. Steiner, Jesse N. Weber, and Hopi E. Hoekstra: The tremendous amount of variation in color patterns among organisms helps individuals survive and reproduce in the wild, yet we know surprisingly little about the genes that produce these adaptive patterns. Here we used a genomic analysis to uncover the molecular basis of a pale color pattern that camouflages beach mice inhabiting the sandy dunes of Florida's coast from predators. We identified two…

I have a quiz for you

This quiz is really low-tech, so I have the questions here, and the questions with their answers below the fold. This is, of course, a self-graded, self-reported quiz. 1) How long did the Hundred Years War last? 2) Which country makes Panama hats? 3) From which animal do we get catgut? 4) In which month do Russians celebrate the October Revolution? 5) What is a camel's hair brush made of? 6) The Canary Islands are named after what animal? 7) What was King George VI's first name? 8) What color is a purple finch? 9) Where are Chinese gooseberries from? 10) What is the color of the…

Giant Green Spiral Over the North Pole

Quick! Its the Santa Signal! Get the Sled, and Rudolph, fast! Or, a spontaneous study of how many people have cell phones with video capability and fast reflexes! Nice pictures and videos! From altaposten.no - click to embiggen altaposten.no story - in Norwegian, natch From NRK.no - with video - good video Daily Mail in the UK has a good photo and video collection This brought out the UFOfans and conspiracy theorists, what with Obama heading for Scandinavia for the Nobel festivities. Youtube video summarizing story, with several views and videos. Youtube summary of pictures and videos…

Warped and Twisted, a Stellar Misfit

HD61005 is a nice normal, young star with a dusty disk that will likely make planets one day. Real soon now in fact. But HD61005, like some other stars, is different. It is warped. Well, the rim of its disk is. Warped disk of HD61005 (click to embiggen) The above picture is a Hubble image with the light from the central star suppressed, showing the extended disk of dust around the star. As you can plainly see, the disk around the star is bent. Question is why? We've seen warped disks around stars, and often there is an apparent reason, such as radiation pressure from another, massive and…

Using a "distributed grid of undergraduate students" to annotate genomes

I just love this title! It's nerdy and cute, all at the same time. I read about this in www.researchblogging.org and had to check out the paper and blog write up from The Beagle Project (BTW: some of you may be interested in knowing that The Beagle Project is not a blog about dogs.) The paper describes a class where students from Marseilles University investigate the function of unidentified genes from a Global Ocean Sampling experiment. All the sequences are obtained from the environmental sequence division at the NCBI. Students follow the procedure outlined below: This is a great…

Bacterial metagenomics on the JHU campus: analyzing the data, part IV

Do different kinds of biomes (forest vs. creek) support different kinds of bacteria? Or do we find the same amounts of each genus wherever we look? Those are the questions that we'll answer in this last video. We're going to use pivot tables and count all the genera that live in each biome. Then, we'll make pie graphs so that we can have a visual picture of which bacteria live in each environment. The parts of this series are: I. Downloading the data from iFinch and preparing it for analysis. (this is the video below) (We split the data from one column into three). II. Cleaning up the data…

How Do You Accidentally Delete Years' Worth of Emails?

Is this the same way that one "accidentally" invades a country, "accidently" sets up offshore subsidiaries to avoid US law, and "accidently" profits off the misery and death of the poor and unfortunate? I think that Rove needs to be "accidentally" deleted from his job. He is, afterall, employed by the people of this nation -- or so the rumor goes. Below the fold are details of how the White House is "accidentally" stretching the boundaries of credulity ... Karl Rove's lawyer on Friday dismissed the notion that President Bush's chief political adviser intentionally deleted his own e-mails…

Advice to the Dems

One of the main themes coming from the punditocracy in the wake of yesterday's election is that the Democrats are making a mistake if they think anyone likes them. This was strictly an anti-Bish result, apparently. If Demcrats start following those lunatic lefty impulses they're prone too, they'll quickly find the country rebelling against them. So much more important that they be bipartisan and centrist. Mike the Mad Biologist and Firedoglake already have good discussions of this issue (available here and here respecitvely.) I would only add to their analyses that precisely the same…

053/366: Mount Rubidoux

Having successfully given two talks in Sacramento, I'm spending a few days visiting my sister in Riverside, CA, because it's not often I'm on the West Coast at all. She had to work this morning, so I went on a bit of a hike up and down Mt. Rubidoux, where the city has built a really nice paved trail that winds around the mountain: Part of the Mt. Rubidoux trail, coming down from the top. I went out at around 9am, which had the advantage of being relatively cool and pleasant for walking. The disadvantage is that there was a ton of fog, making it hard to get good photos from up on the…

A New North American Clean Energy Plan

Barack Obama, Justin Trudeau and Enrique Peña Nieto, have made a joint announcement. As reported by NPR: President Obama and his counterparts from Canada and Mexico are preparing to unveil an ambitious new goal for generating carbon-free power when they meet this week in Ottawa. The three leaders are expected to set a target for North America to get 50 percent of its electricity from nonpolluting sources by 2025. That's up from about 37 percent last year. Aides acknowledge that's a "stretch goal," requiring commitments over and above what the three countries agreed to as part of the Paris…

Watching C-Span

Is there anything scarier than watching C-Span when they have live call-in shows? There are apparently a lot of insane people sitting in their apartments with C-Span on speed dial, just praying for an opportunity to spew their personal pet peeves at the world for 30 seconds. There appears to be some sort of time warp between the people in the studio and the people on the phone. They've got a columnist on this morning talking about railway safety, but Ernie from West Virginia, who has been trying to get through since Thursday, doesn't care. He has something to say in response to Mildred from…

Martian melting

NASA's JPL division has an interesting article on thawing dry ice (frozen CO2) near the polar regions of Mars. Aside from its being interesting, I only bring it up as it reminds me of the faux skeptic talking point about Mars warming, ergo the sun drives warming here on earth.  It is about as far from a truly skeptical argument one could imagine as it rests (or at least it did when it originated) on the flimsiest of evidence that there is climate change on Mars at all.  A truly skeptical approach would not make the leap from two photos of one spot to a global trend.  Even if you establish the…

Gravitational waves will show the quantum nature of reality (Synopsis)

"If you are not completely confused by quantum mechanics, you do not understand it." -John Wheeler Now that LIGO has detected gravitational waves directly, it's time to examine all the different sources that they come from, and what they can teach us about the Universe. While accelerating masses in strong gravitational fields -- black holes, neutron stars and the like -- will produce gravitational waves capable of being seen by direct detection experiments, there's another class of gravitational waves that's observable through its effects on the leftover light from the Big Bang: gravitational…

Could Aliens See Heat-Based Signs Of Life On Earth? (Synopsis)

“The world communicates subtly. Most people don't hear or see the signs because they're so wrapped up in their day-to-day lives.” -Doug Cooper If you wanted to see if a planet was inhabited in Star Trek, all you had to do was scan for signs of life. With current technology, that's really hard to do! We rely on cues from all across the electromagnetic spectrum to identify biosignatures, such as analyzing the atmosphere, land and oceans for molecular signatures. This image from Sentinel-2A shows how Saudi Arabia’s desert is being used for agriculture. The circles come from a central-pivot…

Dorky Poll: Just One Lecture

I unwisely agreed to cover the first class for one of my colleagues with a late-arriving flight back from break before finding out when the class met, which was 8:00 this morning. As a result, my whole morning blog routine was disrupted. I'm saved from having the site go completely dark, though, by an email from a colleague who's teaching a course on science fiction, asking if I'd be interested in doing a guest lecture. I'm open to the idea, but I don't know what I would talk about. So, here are two Dorky Poll questions, one very specific: 1) If I were to do one guest lecture for a class on…

The Open Laboratory Needs More Physics

The indefatigable Bora Zivkovic is soliciting contributions for the science blogging anthology The Open Laboratory. He's titled the post "Last Call for Submissions," but the actual deadline is December 20th. On or about December 19th, I expect a post title along the lines of "Wolf! Wooooolllllfffff!!! Oh My God, a Wolf!" but that's neither here nor there. Being a commmitted advocate of Open Science, Bora has posted the full list of submissions to date. Looking it over, my main reaction is "Where's the Physics?" It's not just that this blog isn't nominated, but a general lack of physics posts…

Sketchy March Meeting Notes: Monday

I'm terrible about taking notes on conference talks, especially when I'm jet-lagged and was sleep deprived even before I got on the plane. I do jot down the occasional paper reference, though, so here are the things I wrote down, and the talks they were associated with. This should give you some vague idea of what the meeting was like on Monday. From Joel Moore's talk on topological insulators, one of the Hot New Topics in condensed matter, a review in Nature. From Phillip Treutlein's talk on optomechanics, a recent preprint on coupling atoms to mechanical oscillators. From Nathaniel Brahms'…

New Development in Zimbabwe: Syphalitic leader Robert Mugabe claims only God can remove him from office.

Well, now it's official. The leader of Zimbabwe is an out of control nut-job who will probably linger in office until very slow moving pressures from outside push him out, or until there is a bloody coup of some kind. This comes after his opposition has publicly considered pulling out of a contested electoral process under threat of increased violence that seems to be perpetrated by Mugabe's corrupt organization. Zimbabwe's President Robert Mugabe says "only God" can remove him from office, as the opposition MDC considers pulling out from a presidential run-off vote. "The MDC will never be…

Steven Pinker on Dangerous Ideas

Steven Pinker of The Blank Slate fame, weighs in on the nature and temptation of "dangerous ideas" in the latest must-read for visitors to the Island. Not too surprisingly, he likes them. Among the questions we should not be afraid to ask, says Pinker, are: * Do parents have any effect on the character or intelligence of their children? * Have religions killed a greater proportion of people than Nazism? * Would damage from terrorism be reduced if the police could torture suspects in special circumstances? An excerpt , from his essay, which is the introduction to a series on dangerous ideas…

The Final Countdown

The Intro Physics II final exam was this week. The signs were all there. 1. It was a summer class. Therefore a fairly high proportion of the students were taking it again after having failed it previously. 2. The class switched professors two weeks before the final. The first professor is a skilled scientist but, well, not necessarily as gifted in passing his skills to his students. 3. The second professor made the final exam from scratch. I just finished grading three problems worth of the final exam (the other two TAs are taking care of the rest), and I think the exam can be safely…

Solar Heat & Thermodynamics

Pop quiz! The picture below is a solar power facility wherein light from the sun is collected by mirrors and focused onto the top of a collecting tower. Fluid within the tower is heated by this light and the hot fluid is used to generate power. We won't care about that in this quiz though; we're just assuming that all the energy goes into heating the tower until its own radiant heat output is equal to that coming in from the mirrors. Here's the quiz setup. There's nothing stopping you from adding as many mirrors as you want to this installation - for the purposes of this question you can put…