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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."
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.
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Free your mind.
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
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.
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"
"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."
If you butter both sides, will it land on its edge?
A better question, what if you butter the edge as well?
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!"
So no problem for most geeks then...
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.
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.
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.
...although less spectacular
l
http://web.mit.edu/newsoffice/nr/1995/40409.htm
if I ever get another story rejected by slashdot, I'll shoot myself
Ever heard of RISC OS It's been around for about ten years now. It was used widely in schools (until Blair started getting chummy with a certain Mr Gates) on British designed hardware by Acorn. Now-a-days the Brits contribute a lot to the open source community. Alan Cox and Russell King are two notable personalities.
I for one definitely don't say give me microsoft and probably use more european software than american software. My hardware is mainly Taiwanese, Korean or Japanese except for the SGIs. The US is definitely not the fount of all knowledge and technology.
But when it comes to making an Operating System or even choosing one for their schools, they simply turn to America and say, "Give us Microsoft". Amazing.
It was not always the way. After all, business computing began here with the Lyons Electronic Office, and in the 80's schools used the BBC Micro, developed by Acorn in Cambridge.
The rot didn't set in until the 90s, and a once thriving British computer industry went down the pan. For shame.
I blame the government. It doesn't help when we have a PM keen to lick arse, whether that arse be Bill Gates' or Dubya Bush's.
"Information wants to be paid"
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).
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 ...
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.
This is one of the least trollish comments I've read on this thread (though that isn't saying much). This guy just described my life spot on. I'm neither American nor fat, but in both cases I can only thank my parents. There but for the grace of god go I.
Considering this is an article about one of the many traditional annual face-stuffing days westerners celebrate, it's hardly trolling to point out how many people have, or think they have, no time to get any excercise.
Stressed-out, over-fed, under-excercised = early death. The solution is not to diet (=less food, but more stress and still no excercise), but to get plenty of excercise (helps with stress, and you can eat all you like because your body turns it into muscle or motion rather than fat).
In my final year at university, I quit smoking and started swimming just under a mile four times a week. It was the best six months of my life - I was relaxed, I had plenty of energy, muscles even started appearing! Then the exams came along, followed by life as a code-monkey, and here I am smoking, lazy, stressed and eating like a vacuum cleaner. Time to resurrect that lapsed gym membership, I think.
"The Milliard Gargantubrain? A mere abacus - mention it not."
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.
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.
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.
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.
Every day they sit and worship a device invented by John Logie Baird, a Brit.
"I am not bound to please thee with my answers" [William Shakespeare]
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.
And parlimentary democracy was instituted in the 13th Century with the signing of the Magna Carta. By the 17th Century we'd had a civil war during which the King was removed from power and only parliment ruled the country. So Britain was a democracy at least a century before the American Revolution
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!"I think the Athenians have prior art. You can have credit for the court system, with seperate judge, jury, and executioner, though. That, in my opinion, is as or more important.
"The question of whether a computer can think is no more interesting than that of whether a submarine can swim" -EWD
Pancake Algebra
not quite the same, but thoroughly enjoyable !
Francis.
(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.
File under 'M' for 'Manic ranting'
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.
1) Hang-time of the pancake:
2)Time for a 180 degree flip:
3)Starting spin condition:
4) I can substitute equation 3 into 2 to get:
5) The pancake radius cancels out!
6)Then, I set the two times equal to eachother, because we are looking for the time to flip to be exactly the hang-time:
7) Solve for angular velocity...
8) The condition at Launch is
9) So, by 7 and 8, (substituting V)..
10) which is the same as
This result is just a clean factor of two off from the article. I'm very suprised that I can put together enough physics to derive something that is apparently so newsworthy!
now someone help me find the mistake!
Raisinettes are my raison d'etre