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November 14, 2012

Daily [Intermittent] Open-Ended Puzzle: Camera shutters

Why do digital SLR (single lens reflex) cameras have shutters?

In analog days, the shutter let light in for some determinant time. That caused the film to be exposed for that duration. But in the digital age, why doesn’t “setting the shutter speed” just tell the internal computer how long it should record data from the sensor? What good does it do to actually open and close a physical shutter?

Just curious. And probably misinformed.


March 22, 2011

[doep] Daily (intermittent) Open-Ended Puzzle: Why do moths fly the way they do?

My understanding (possibly bogus) is that moths spiral into flames because evolution has designed them to fly in straight lines by noting celestial lights. When the light is nearby, keeping its position fixed in their visual space causes them to spiral inward toward it.

Fine. But why is it an evolutionary advantage for moths to fly in a straight line? Where are they trying to get to so quickly? And isn’t there a metaphor for MBAs somewhere in here?

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March 6, 2011

[doep] Daily (Intermittent) Open-Ended Puzzle: Dig a hole…

The following is an Order of Magnitude puzzle: Guess within an order of magnitude of the answer and you win! You win nothing!

If you were to start any spot on land on Earth and dig a hole through the center of the Earth, what percent of the time would you come out on another spot on land, as opposed to having water spray out, comically spinning the Earth out of orbit to its death? (To be precise, the question isn’t about water spraying or not spraying out of the hole. It’s about the percentage of times you’d hit land.)

The answer is in the comments. But, wait, to help you, this fabulous mashup using the Google Maps API will let you sink your own knitting needles through the Earth’s nougaty core!

(All of this came from a mailing list I’m not supposed to acknowledge. Answers authenticated by the good folks at Wikipedia.)


February 20, 2010

Order of Magnitude Quiz: Patents

How many patents do you think there are in the United States? (I believe that the number that I have, which comes from Beth Noveck’s excellent Wiki Government, refers to the number of patents in effect.)

Because this is an Order of Magnitude quiz, you win if your answer is within one order of magnitude of the right answer.

The right answer is in the first comment.

Note: Winning means that you win nothing. Just to be clear.


August 19, 2009

Order of Magnitude Quiz: The cost of street lights

Facing a budget shortfall, the town of Andover, MA, has decided to turn off 600 streetlights, leaving 900 on. How much do you think that will save Andover per year, according to the article in the Boston Globe?

This is an Order of Magnitude Quiz, which means you win if your answer is correct within an order of magnitude. It also means, however, that there’s nothing to win.

Click here for the answer

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August 8, 2009

Daily (Intermittent) Open Ended Puzzle [DOEP]: Optimal speed

Thirty years ago, we were told that we should drive 55mph (or, in Europe, 42 euros per hectare) on the highway because that was the “optimal” highway speed when it came to squeezing miles out of gallons.

What is the current optimal highway speed?

And, for extra credit, what is the optimal speed on or off the highway? If I want to get maximum miles per gallon but don’t care how fast I go, how fast should I drive? Two caveats: Yes, I know this will be different for different cars in different conditions. And, no, zero mph is not an acceptable answer, no matter how true it is.

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May 30, 2009

Daily (intermittent) Open-End Puzzle (DOEP): Fattening yogurt

This is a “Let’s figure out how this statement might be true” puzzle. I have an answer in mind (which you probably won’t like), but I’m more interested in the ones y’all come up with:

For the sort of run-of-the-mill yogurt — no fruit on the bottom — you buy in your average American supermarket, I believe it is true that the further you go down in the container, the more fattening it becomes.

Why might that be true? More important, in how many different ways can we take that putative fact to make it true?

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November 20, 2008

Daily (Intermittent) Open-Ended Puzzle: Monty Python headlines

Monty Python has announced that it’s making all many of its works available for free on YouTube. Yay!

What is the best Python-referencing headline for a post announcing this? “A hovercraft full of reels”? “Not pining for the fee(ords)”? “Wring out your dead”?

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September 6, 2008

Daily (intermittent) Open-Ended Puzzle: Crowd-sourcing bagels

When I was in Norway last week, in a shopping arcade in Kristiansand there was a bakery selling sandwich bagels. The bagels seemed to have categorized as such simply because they were tori made out of bread: ovoids eight inches in diameter and about as high as the edge of a pizza crust. Was this the least bagel-like bagel on the planet?

This is something only the wisdom of the crowds can answer. If you’ve come across a national, regional, or industrial version of a bagel that is less bagel-like, let me know. Otherwise, the laurel will remain on Kristiansand’s brow. (It’s a lovely city. I just wouldn’t go there for the bagels.)

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July 19, 2008

Daily (Intermittent) Open-Ended Puzzle (DOEP): The triple negation of butter

We often buy “I Can’t Believe It’s Not Butter” despite its awful name and soul-withering chemical composition. Even the product’s faux-entertaining site refers to it as a “nutritious blend of oils.” Mmm. But, I like it, so shut up.

In fact, we just bought the “light” version of it, which is therefore some sort of simulacrum of the original. I can’t figure out whether its name should therefore be:

1. “I Can’t Believe I Can’t Believe It’s Not Butter”

2. “I Can’t Believe It’s Not Not Butter”


3. _______________________ (fill in the blank)

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