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Pancake Physics to Cut Batter Splatter

Anonymous Coward writes "The headline just about says it all on this one. A physics grad student in the UK has come up with the mathematical formula for how to flip a pancake and have it land correctly back in the pan. The BBC has the details."

31 of 298 comments (clear)

  1. Ah-hah! by Gortbusters.org · · Score: 4, Funny

    His secret is revealed: The angular velocity of the object equals the square root of Pi, times the gravity divided by the distance the pancake is from the elbow times four - that is how to get the pancake back in the pan.

    Seriously, mimicing real life movement in mathematical forumla is a tough one (that's why we don't see any battlemechs walking around, or tons of popular robots in every house hold.

    --
    --------
    Free your mind.
  2. Pancakes, crepes, flapjack... by marnanel · · Score: 5, Informative

    Americans should bear in mind that what are called "pancakes" in England are called "crepes" in America. What are called "pancakes" in America are called "Scotch pancakes" in the south of England, and "drop scones" in Scotland and the north of England. Meanwhile, "flapjacks" are a kind of oaty biscuit. Confused yet?

    --
    GROGGS: alive and well and living in
    1. Re:Pancakes, crepes, flapjack... by Xxanmorph · · Score: 5, Funny

      Too much information about other countries! My american brain can't take it!

  3. I'm gonna nit pick. by Boss,+Pointy+Haired · · Score: 4, Insightful

    It will make sure the pancake will land back in the pan, as long as you understand the formula.

    Understanding something does not equate to being able to do it.

    I understand how a plane flies, but I can't fly one.

    1. Re:I'm gonna nit pick. by ender81b · · Score: 5, Insightful

      Heh. I'm a line cook here in the US and there is quite a bit more to flipping American Pancakes (I realize english pancakes are somewhat different).

      Stuff like how long you wait till you flip it, the perfect angle to get the spatula underneath the pancake (directly parallel to both the grill and the pancake), what to do with blueberry/raspberry/banana/etc pancakes, what to do when the cake sticks, and the rest. I'm sure you could come up with an equation to perfectly predict this and it wouldn't mean a damm thing -- like this one.

      I mean you could equally use a formula to try and tell somebody how to flip eggs and it wouldn't meen a damm thing. To train line cooks to flip the proper, and perfect, Over Easy egg requires about 100-200 wasted eggs until you get it down to about 95% of the time -- and that extra 5% is a pain since each egg varies in how much force will require before it breaks, etc and usually requires thousands of eggs before you can go nearly an entire 8 hour shift without breaking at least 1 yolk open. By 'flip' an egg I mean using only your wrist, no sissy spatulas involved. It takes alot of work and effort to learn to do these things which is why almost nobody outside cooks can probably cook eggs or omeletes the *right way*, no spatulas/informercial specials involved.

    2. Re:I'm gonna nit pick. by arvindn · · Score: 4, Insightful
      You are mistaken.

      http://catb.org/esr/jargon/html/Some-AI-Koans.html :

      A novice was trying to fix a broken Lisp machine by turning the power off and on.

      Knight, seeing what the student was doing, spoke sternly: "You cannot fix a machine by just power-cycling it with no understanding of what is going wrong."

      Knight turned the machine off and on.

      The machine worked.

      In the same way, the pancake will land back in the pan as long as you understand the formula.

      [[Mods, mods: this is supposed to be _funny_. Its not the first time I've posted something hilarious and it got modded "Insightful"]].

    3. Re:I'm gonna nit pick. by fyonn · · Score: 4, Funny

      Are you a geek? Be proud of it. Prove it. Memorize 1000 digits of pi!

      I can remember *all* of the digits to pi

      now the order.. thats a different matter...

      dave

  4. Sounds good by trotski · · Score: 4, Interesting

    But since most of us geeks are pretty inept when it comes to anything physical, I still think my pancakes gonna land on the floor, no matter what formulas I apply.

    Now if we could only have some kind of a pancake flipping robot.....

    --

    "Entropy is the bad-guy, and he is everywhere"
  5. In other news by djupedal · · Score: 3, Funny

    "A pancake in the UK has come up with the mathematical formula for how to flip a physics grad student and have him land correctly back in the pan. The BBC has the details."

  6. Butter! by Anonymous Coward · · Score: 4, Funny

    If you butter both sides, will it land on its edge?

    A better question, what if you butter the edge as well?

    1. Re:Butter! by Ashtead · · Score: 5, Funny
      Actually, the study of bread falling off table was taking into account the starting position which is on the table and with the buttered side up. Seems the height of the table and the inertial torque of the bread conspire to make it roll somewhere between 1/4 and 3/4 turns, and therefore fall face down more often than not. With subsequent need for cleanup. If the table had been about twice as tall as a standard table (60 in instead of 30 in) the pieces of bread would have time to tumble one full turn and thus fall face up.

      Falling cats are famously able to turn around and land on their feet. Unless the height of the fall is too large, the cat has no problems with that. I forgot the exact conditions of falling cats, but they are able to turn around in a fall in a lot less than the 30 inches down from a table.

      If the two were to be combined and the cat has a piece of bread strapped to it, it is the cat that prevails, being more active, heavier, and having a larger moment of inertia.

      I'd imagine that the same would apply to pancakes, and I have disregarded the risk of the cat eating the food.

      --
      SIGBUS @ NO-07.308
  7. Shrove Tuesday (why the BBC ran the story then) by WebfishUK · · Score: 5, Informative



    Not sure about other countries but last Tuesday (4th) was Shrove Tuesday in the UK when we all make pancakes. For the religious amongst you the word 'Shrove' refers to the practice of confessing of sins, then afterwards the fast of Lent could be considered a penance of faults committed. Thats why the BBC ran the story on Tuesday. However, most of us just love eating the pancakes!

    --
    -- "Can't sleep, clowns will eat me!"
    1. Re:Shrove Tuesday (why the BBC ran the story then) by HumanXX · · Score: 3, Informative
      Shrove Tuesday is the day before Ash Wednesday, the start of Lent, the period of 40 days leading upto Easter where people would originally go without eating various dairy products for that period. History was that people would use up all the eggs, and milk in the house, so someone came upon the idea of making pancakes.

      I made some cracking pancakes on Tuesday, my special recipe involves grating bits of lemon and lime rind into the batter, mmmmm, that citrus flavour flows all through the pancakes, nice.

      I am not religious but it is always useful to know about as many different religions as possible as this gives you many excuses to feast, well that and setting off lots of fireworks.

  8. Apparently it's all in the wrist action... by Boss,+Pointy+Haired · · Score: 4, Funny

    So no problem for most geeks then...

  9. Is that.... by Highwayman · · Score: 3, Funny

    Is that Hans Blix in the article's photo? I long have expected the UK to be in possession of a proscribed pancake making machine able of launching a pancake in excess of 150km. In other news, Rumsfeld demands accounting for 1.5 tons of missing pancake batter.

  10. BBC doesn't understand it by panurge · · Score: 4, Informative
    The BBC quotes a garbled version of the equation (haven't they got an equation setter? cheapskates) but clearly don't understand what it means.

    AFAIUI it simply means that the pancake needs to spin at such a rate that it will flip 180 degrees between leaving the pan and returning. Given that it will not fall back flat unless the flip is 180n degrees, n integral, this is pretty blindingly obvious.

    Unfortunately, the equation is just that and doesn't tell you how to achieve flip rate nirvana. So here is my guide:

    • First, use a nonstick pan with a gently sloping edge.
    • Second, use just enough oil to ensure the crepe can slide around smoothly.
    • Third, in order to flip, start by lowering the far edge of the pan so the crepe starts to slide towards the edge.
    • Then, as the crepe reaches the edge, rotate the elbow upwards so that the crepe slides off the edge in an upward direction. This provides the spin. The speed doesn't need to be too high. As the crepe flips over, catch it with the pan horizontal.
    • Start with small crepes and build up.
    • When I was first shown this technique in a creperie in Normandy, by the end of the evening I could flip them up to ceiling height and still recover them.
    Creperies that use precooked crepes made on industrial conveyor belts are of course beyond the pale.
    --
    Panurge has posted for the last time. Thanks for the positive moderations.
  11. Actually... by Anonymous Coward · · Score: 5, Funny

    I think you meant:

    In Heaven, the police are British, the lovers are Italian, the cooks are French, the engineers are German, and it's all organized by the Swiss.

    In Hell, the police are German, the lovers are Swiss, the cooks are British, the engineers are French, and it's all organized by the Italians.

  12. Re:Amazing Brits... by freddled · · Score: 5, Funny

    We are having a rest after inventing democracy (o/s for civilisation), the English language (o/s for culture and arguably thinking), Football (conflict resolution and war emulation) and Cricket (cultural add-on for massively-scalar beer drinking in the park).

  13. Re:Amazing Brits... BCPL by Burb · · Score: 3, Informative

    Oh yes, and if you look in your history books you'll find that C owes a lot to a certain language called BCPL developed by Martin Richards at Cambridge University in the 60's ...

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  14. err by Geaty · · Score: 5, Interesting
    The angular velocity of the object equals the square root of Pi, times the gravity divided by the distance the pancake is from the elbow times four

    hmm . . . I notice that this formula does not factor in mass of the pancake. this makes me wonder, being not-so-smart in physics, would this formula apply for any size pancake?? and how about objects other than pancakes? could I flip say, a thanksgiving turkey and still have it land perfectly in the pan, using this formula??

    and why do Scots like cheese in their pancakes?? don't they know the proper way to do anything is the American way, i.e. sugar and syrup??

    Bored and tired minds want to know!!

    --
    All I ever wanted was an honest week's pay for an honest day's work.
    1. Re:err by gilroy · · Score: 3, Informative
      Blockquoth the poster:

      hmm . . . I notice that this formula does not factor in mass of the pancake. this makes me wonder, being not-so-smart in physics, would this formula apply for any size pancake??

      In problems driven solely by gravity, the mass typically drops out. Thank you, Equivalence Principle.

      and how about objects other than pancakes? could I flip say, a thanksgiving turkey and still have it land perfectly in the pan, using this formula?

      A pancake is a nicely simple and symmetric object. Indeed, the symmetry means that whenever you flip it, you're doing so about a stable axis. Other shapes, not so nice... your turkey might tumble wildly. Also, while the mass drops out of the angular velocity, it does not drop out of the formula for the needed force -- and a turkey tends to be quite a bit more massive than a crepe.
  15. Re: In England we're real tossers by Amroarer · · Score: 5, Informative

    Well, where I come from, we don't use no spatulas to toss pancakes... (Although some more cautious people do slip them out of the pan onto a plate, then drop them back in upside down.) English pancakes are so wide and thin that a spatula's likely to just tear them. Instead you have to use the showing-off-method.

    First you make a circular movement with the pan to ensure that the pancake hasn't stuck and overcome static friction.

    Then you tilt the end of the pan down slightly and make a short, sharp inward movement, to get the pancake sliding outwards.

    Then you sharply flick the pan up, so that the pancake goes between one and two feet in the air (more if you're feeling cocky) and also spins enough that it lands in the pan the other way up.

    I'll be very impressed if they invent a machine which can repeatably toss pancakes. There are an awful lot of variables, which he seems to ignore. But then he is a physicist, not an engineer. ;-)

  16. This is what Brits have to say about it by Nemosoft+Unv. · · Score: 5, Interesting

    I asked a (native) British collegue about it, and this was his reply:

    Ahh the wonders of pancacke day or as the French call it Mardi Gras Fat tuesday. This is the day before the start of Lent (crazy Christian starvation festival, preparing mind and body for the Easter celebrations etc). Typically people used to use up all their fatty things on this day such as butter, eggs and lard etc, coz it was not the done thing to be eating lard cakes when everybody else was eating celery.

    Thus the pancake tradition started. Of course, all the religous nonsense has largely disappeared but the pancakes remain in British Culture.

    As far as the tossing equation goes, thats just the work of a whacked out English ale swilling academics, and is an essential part of British inventiveness and ingenuity. (You can't make great discoveries all of the time)

    Hope that helps and thank you for your interest in Britain.

    :-)

    --
    "Fix it? It has been disintegrated, by definition it cannot be fixed!" - Gru in Despicable Me.
  17. Okaaaaaay, by DongleFondle · · Score: 5, Funny

    I do believe it is time that someone introduced Europe to the concept of the 'spatula'. We sort a solved this whole pancakes on the floor dilehma a looooooooong time ago . . .
    You know what? While we're at it, let's give China forks and spoons.

  18. Off topic but... by the_pooh_experience · · Score: 4, Informative

    I know this is really off topic, but it is on, if the topic is "reasonibly absurd science". In Nature last December, they decided to publish a short note about an Austrailian matehmatician's work on The Best Way To Lace Your Shoelaces

    No joke.

  19. Something going wrong.... by isa-kuruption · · Score: 3, Insightful

    There is something seriously wrong with the education system when a grad student gets a masters in physics for writing a thesis on flipping a pancake.

    What's next? Maybe, for his doctoral thesis, he should write a formula for the proper amount of syrup to be used based on it's rate of obsorbtion by the pancake.

  20. Re: In England we're real tossers by WolfWithoutAClause · · Score: 3, Funny
    I'll be very impressed if they invent a machine which can repeatably toss pancakes. There are an awful lot of variables, which he seems to ignore. But then he is a physicist, not an engineer. ;-)

    Yeah, but that means he will be more accurate by roughly 5% because he won't be assuming that pi is 'nearly' 3 ;-)

    --

    -WolfWithoutAClause

    "Gravity is only a theory, not a fact!"
  21. Pancake Algebra, it actually exists... by lonedfx · · Score: 3, Informative

    Pancake Algebra

    not quite the same, but thoroughly enjoyable !

    Francis.

  22. Does anyone else see a flaw in this formula? by mark-t · · Score: 3, Insightful
    The angular velocity is, according to the formula:

    (sqrt(pi)*1g)/(d*4)

    Where g is the accelleration due to gravity and d is the distance from the elbow to the pancake.

    In addition to the rather obvious (or at least intuitive) flaw of not considering the size/mass of the pancake, this formula cannot possibly produce the value claimed. Dimensional analysis shows that it results in an answer measured in terms of radians per second squared, and angular velocity is always measured in just radians per second.

    Of course, if they *meant* to say angular accelleration, they should have said so.

    1. Re:Does anyone else see a flaw in this formula? by Redwing · · Score: 3, Insightful

      The problem seems to be in the interpretation of the english representation of the equation:

      The angular velocity of the object equals the square root of Pi, times the gravity divided by the distance the pancake is from the elbow times four

      You took this to be :

      (sqrt(pi)*1g)/(d*4)

      when it should be interpreted as:

      sqrt( pi*g / (d*4) )

      then you get the right units.

      --
      Raisinettes are my raison d'etre
  23. Re:Amazing Brits... by Greedo · · Score: 3, Funny

    Only on Slashdot can a post on linguistic differences about the term "pancakes" result in an anti-Microsoft reply within two posts.

    There should be a Six Degrees of Slashdot test: how many posts does it take to turn a discussion into one about operating systems, beowulf clusters, or the RIAA.

    --
    Tuus crepidae innexilis sunt.