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Me I'm 74% savvy
August 24, 2008 12:59 PM   Subscribe

Are you savvy metaboffs?
posted by chelegonian (101 comments total) 6 users marked this as a favorite

 
87.5%
posted by tkolar at 1:11 PM on August 24, 2008


75%
posted by Solon and Thanks at 1:12 PM on August 24, 2008


metaboff?
posted by octothorpe at 1:22 PM on August 24, 2008


Well, that was lame.
posted by AsYouKnow Bob at 1:27 PM on August 24, 2008 [1 favorite]


77.5%
posted by XMLicious at 1:28 PM on August 24, 2008


That sounds like something we'd do on a subsite Matt has yet to launch, and one that would cost $4.99 a minute to use.
posted by orange swan at 1:32 PM on August 24, 2008 [3 favorites]


Metaboff, that is.
posted by orange swan at 1:33 PM on August 24, 2008


Well, that was lame.

You missed that many, huh?
posted by tkolar at 1:33 PM on August 24, 2008 [4 favorites]


82.5%, and I'm astonished. I was pretty decent at physics back in high school, but that was 40 years ago. (Also, my answer about clouds was dumb. Use your head, 'hat!)
posted by languagehat at 1:35 PM on August 24, 2008


65%.

Stupid quiz.
posted by Bookhouse at 1:36 PM on August 24, 2008


92.5 but I should've got them all really. This is basic stuff. I mean I barely passed 1st year physics with a c+ and only took that because it was a requirement and I still should have known them all.
posted by juv3nal at 1:38 PM on August 24, 2008


65%, more or less equals my overall mark in highschool physics.
posted by maxpower at 1:39 PM on August 24, 2008


75%, pretty good since I know little to nothing about kinematics or fluids.

Boffin: n. Chiefly British Slang — A scientist, especially one engaged in research.
posted by furtive at 1:40 PM on August 24, 2008


80% which, imho, is pretty damn good since I'm a philosopher not an engineer. Kinematics did me in.
posted by oddman at 1:43 PM on August 24, 2008


Yay, 90%!
posted by martinrebas at 1:46 PM on August 24, 2008


95%. Argh, and I knew that trick question about the direction electrons move.

Also: stupid clouds.
posted by supercres at 1:49 PM on August 24, 2008


Answer key: assume that your intuition is wrong.
posted by supercres at 1:52 PM on August 24, 2008 [4 favorites]


85%. And this question didn't say how fat Susan was.

Susan jumps off a chair. As she is falling, the Earth’s gravitational force on her is higher than her gravitational force on the Earth.
posted by dances_with_sneetches at 1:54 PM on August 24, 2008


I answered each one "false" and got 67.5%.
posted by Marie Mon Dieu at 1:55 PM on August 24, 2008 [1 favorite]


85%
posted by orthogonality at 2:00 PM on August 24, 2008


Yippee -- 95 %. The two I got wrong were the ones about what clouds are made up of and the force that pushes electrons through wires.
posted by peacheater at 2:06 PM on August 24, 2008


85%. And this question didn't say how fat Susan was.

Susan jumps off a chair. As she is falling, the Earth’s gravitational force on her is higher than her gravitational force on the Earth.


It doesn't matter -- the gravitational force one object exerts on another is always equal to the gravitational force exerted by the other object on it.
posted by peacheater at 2:07 PM on August 24, 2008


I suck. 40%. Thank goodness I don't teach this stuff.
posted by davidmsc at 2:15 PM on August 24, 2008


Yippee -- 95 %. The two I got wrong were the ones about what clouds are made up of and the force that pushes electrons through wires.

Same here. I also missed the temperature one.. I guess it took me a couple of questions to get into the right mindset.

Also, it was lame! Most questions tested reading comprehension more than scientific understanding, in my opinion.
posted by Chuckles at 2:25 PM on August 24, 2008


67.5%. But, to my credit, most of the ones I got wrong had very long explanations.
posted by cyclopticgaze at 2:31 PM on August 24, 2008 [3 favorites]


85%. And this question didn't say how fat Susan was.

Susan jumps off a chair. As she is falling, the Earth’s gravitational force on her is higher than her gravitational force on the Earth.

It doesn't matter -- the gravitational force one object exerts on another is always equal to the gravitational force exerted by the other object on it.


Yer mamma's so fat, the interactions between her body and the Earth's gravitational field defy conservation of energy.
posted by XMLicious at 2:37 PM on August 24, 2008 [14 favorites]


Argh. Science.
posted by saturnine at 2:38 PM on August 24, 2008


85% - a good example of the sorts of stuff all high schools students should be taught. I'd forgotten or become less precise about a couple answers and I learned a thing or two about a couple others.
posted by meinvt at 2:39 PM on August 24, 2008


mmmmm savory meatboffs.
posted by kuujjuarapik at 2:39 PM on August 24, 2008 [2 favorites]


88%, because I figured out that they are cranky, so most answers are false.
posted by StickyCarpet at 2:40 PM on August 24, 2008


What good is physics anyway? Does it help me convert food into energy, or keep a roof over my head, or get from A to B, or make my car go really fast, or stop me from spinning off into space due to the Earth's rotation? Didn't think so! More like FAILsics!
posted by turgid dahlia at 2:43 PM on August 24, 2008


If the Lord Jesus Christ had wanted us to take online surveys, our hands would have been distinctively molded in the shape of a submit button.
posted by Rhomboid at 2:55 PM on August 24, 2008


92.5! I, too, missed the idiotic water vapor in a cloud question.
posted by Justinian at 3:01 PM on August 24, 2008


45%. Perhaps my scheme of learning science painlessly through reading science fiction books should be reexamined.
posted by mygothlaundry at 3:03 PM on August 24, 2008 [5 favorites]


85% - I blame (credit?) violent video games.
posted by b1tr0t at 3:05 PM on August 24, 2008


Under typical conditions, ice melts and water freezes at the same temperature.

Quiz says true. I said false. Wikipedia agrees with me:
In spite of the second law of thermodynamics, crystallization of pure liquids usually begins at lower temperature than the melting point, due to high activation energy of homogeneous nucleation
Stupid quiz.
posted by xchmp at 3:22 PM on August 24, 2008 [1 favorite]


At least 8 inches, but I haven't measured in a while, might be bigger.

Wait, what were we talking about?
posted by sondrialiac at 3:26 PM on August 24, 2008 [1 favorite]


No, sondrialiac, it's about how long you can keep a hadron.
posted by XMLicious at 3:37 PM on August 24, 2008 [4 favorites]


We won't really be able to answer that until the Large Hadron Collider destroys the world. Or not.
posted by lukemeister at 3:45 PM on August 24, 2008


72.5%...color me pleasantly surprised!
posted by mdonley at 3:48 PM on August 24, 2008


I got bored halfway through and tuned out, which I guess means that not much has changed for me since school.
posted by kittens for breakfast at 3:48 PM on August 24, 2008





I answered each one "false" and got 67.5%.


If I had decided to try that I would undoubtedly have chosen 'true'

Instead I humiliated myself with 53%. Oh well. Beats 32.5%
posted by notreally at 4:34 PM on August 24, 2008


100%, but that's probably because on a couple questions, I guessed what they were really getting at rather than what the question actually led you to believe. And probably because I have a degree in this sort of thing.

For example on the engine question, it asked if 100% of the energy would go to moving the car assuming no heat transfer and 100% of the fuel burned. In this case, the wording of the question implies that you are to suspend your disbelief of "100%" efficiency because they've already done 2 impossible things. However, they scored that with the explanation "there is no perfect engine" which is bullshit, since there's no fuel that burns 100% and no engine that has no heat transfer.

So I call bullshit on at least some of these questions.
posted by chimaera at 4:48 PM on August 24, 2008 [4 favorites]


I'm not sure if I should be pleasantly surprised at 82.5% given it has been 30+ years since my last physics class, or annoyed that I got so many wrong.
posted by CheeseDigestsAll at 4:50 PM on August 24, 2008


chimaera: I agree with you. That was one of the three I got wrong. I knew full well there isn't such a thing as a perfect engine, but from the way they worded the question I figured it was one of those things we were supposed to assume was possible, like a fuel burning with 100% efficiency.
posted by Justinian at 4:59 PM on August 24, 2008


For example on the engine question, it asked if 100% of the energy would go to moving the car assuming no heat transfer and 100% of the fuel burned. In this case, the wording of the question implies that you are to suspend your disbelief of "100%" efficiency because they've already done 2 impossible things. However, they scored that with the explanation "there is no perfect engine" which is bullshit, since there's no fuel that burns 100% and no engine that has no heat transfer.

This one isn't bullshit. The amount of work that can be extracted from an engine is limited below 100% due to the laws of thermodynamics and entropy, which have to be considered separately from the efficiency of combustion and the friction of the moving parts. That's what they were aiming at.
posted by yath at 5:02 PM on August 24, 2008 [2 favorites]


50% How's that for middle-of-the-road?!
posted by crossoverman at 5:07 PM on August 24, 2008


82.5% - not bad, I think. Even though I could tell they were worded carefully, I also think a few of them could have been written a little differently... though I suppose that not answering a question correctly because I didn't understand it would indicate a lack of knowledge.
posted by OverlappingElvis at 6:05 PM on August 24, 2008


95%, yeehaw. Also: metaboff.
posted by penduluum at 6:41 PM on August 24, 2008


I got 100%, but with the same caveat chimera listed.
posted by phrontist at 7:38 PM on August 24, 2008


90%. Clouds (if it's water and it's in the air and it's not falling, it must be water vapor, right?), water freezing/melting point (I think they're wrong, or at least the question was misleading), voltage (misled by EMF), ml=cc (had a vague memory of the fact that they used to be different, and was expecting a trick question). Still, not terrible for an aging computer geek.
posted by Crabby Appleton at 8:06 PM on August 24, 2008


95% but frankly I think their questions and explanations suck big-time.
posted by polyglot at 8:14 PM on August 24, 2008


97.5.... dang trick question! Which one, you ask? nope, ain't gonna tell.
posted by drhydro at 8:20 PM on August 24, 2008


77.5%. Better than I was expecting of myself.
posted by jclovebrew at 8:31 PM on August 24, 2008


80% and they're wrong!
posted by zengargoyle at 8:50 PM on August 24, 2008


I got 80%, which is actually really, really sad since I'm just starting my graduate degree in mechanical engineering. I definitely read a number of the questions flat out wrong (even after reading a couple of them more than once), and I call BS on the melting/freezing question.

The rest, well, I guess I'm just dumb. Oh well. Better hit the books.
posted by malthas at 9:00 PM on August 24, 2008


This one isn't bullshit. The amount of work that can be extracted from an engine is limited below 100% due to the laws of thermodynamics and entropy, which have to be considered separately from the efficiency of combustion and the friction of the moving parts. That's what they were aiming at.

I know that was what they're aiming at, but I stand behind my assertion that it is a bullshit question. The efficiency of anything is limited by laws of thermodynamics. So why is it unreasonable to proceed with the answer when the questioner was asking us to suspend doubt regarding efficiency?

A properly worded question would go more like this:
6) Accounting for energy losses due to friction and unwanted heat transfer, could an internal combustion engine be built for an automobile which would be capable of converting 100% of the remaining available energy from combusted gasoline into energy used for moving the car?
You see, this would not require us to presume any physically impossible conditions. No need to ignore heat transfer or friction, you're explicitly told to ignore those contributions, and no need to assume 100% of the gasoline molecules have burned because it says "available energy from combustion."

Therefore the answer would be unmuddied by the fact that you're required to waive the second law of thermodynamics on the premises but re-apply precisely the same law to the conclusion.
posted by chimaera at 9:04 PM on August 24, 2008 [2 favorites]


Therefore the answer would be unmuddied by the fact that you're required to waive the second law of thermodynamics on the premises but re-apply precisely the same law to the conclusion.

But, does "friction and unwanted heat transfer" account for all the energy loss mechanisms? I think it depends on what you mean by unwanted heat transfer.. I mean, a certain amount of energy has to go out the exhaust pipe, or the exhaust pipe stops working, and there must be lots of other systems in an engine that rely on the same principle. In theory, the sum of all that necessary, and hence wanted, energy loss can be arbitrarily small, but never zero.

I agree though, it is kind of a poor question. But like I said, the entire test is more about use of language than science..
posted by Chuckles at 9:18 PM on August 24, 2008


There are an awful lot of places that the energy goes. Some tiny fraction of it even goes into the elastic deformation of the parts themselves while the engine is running. That deformation, which can in certain materials be as small as down to some multiple of the diameter of the atoms, generally becomes heat energy -- therefore it's not heat transfer by conduction (on short time scales radiation/convection play an even smaller role) -- it's mechanical motion -> elastic deformation -> heat.

That question (and the cloud vapor one) was just plain awful.
posted by chimaera at 9:22 PM on August 24, 2008


If your engine can do one impossible thing, it can do a second impossible thing. (Assume a third impossible thing). True of False?

Hmm... score well enough for an A, and then still argue over the questions? Yeah... guess not much has changed since school for me either. :)
posted by adamt at 9:28 PM on August 24, 2008


I think *unwanted* heat transfer is the key. The burning fuel still makes heat, which means an efficiency lost; it's just that the heat goes out with the exhaust gases instead of into the engine block. This means the engine can't be converting *all* the energy to motion; it still loses energy to heat.

I got it wrong, too.
posted by five fresh fish at 9:36 PM on August 24, 2008


60% - not bad, considering I spent most of my time in 9th grade physical science counting the number of times per hour my teacher raised his eyebrows and pushed up his glasses (he averaged about 56).
posted by amarie at 9:37 PM on August 24, 2008


80%. I think there were some tricky questions in there, though.
posted by pjern at 9:47 PM on August 24, 2008


100%, but I've seen a "water vapor" trick question before. 6 and 8 are both heat engine questions -- you can do work with thermal energy when you transfer heat from a higher to a lower temperature. If you wanted to convert all the thermal energy into work, you have to avoid increasing entropy (which the hypothetical engine in question 6 might do), and you have to dump entropy out of the system without losing heat, meaning that the cold reservoir (the engine's exhaust) has to be at 0 Kelvin, which isn't allowed.

This is really 19th century physics, figured out by people who wanted to build better steam engines, but it isn't taught well.
posted by rossmik at 10:12 PM on August 24, 2008


PS: One person who does teach entropy well is Hans Christian Von Baeyer, author of Maxwell's Demon: Why Warmth Disperses and Time Passes. This is an excellent explanation in layman's terms, but it should also be required reading for thermodynamics students.
posted by rossmik at 10:26 PM on August 24, 2008


70% not bad after 25 years of no physics, my weakness is the newton's laws
posted by infini at 10:33 PM on August 24, 2008


Can someone explain the bug vs. train thing? I can't understand how they're exerting the same amount of force. I know which one I'd rather be struck in the face with.
posted by Deathalicious at 10:37 PM on August 24, 2008


Every action has an equal an opposite reaction, so the force the bug exerts on the train is the same as the force the train exerts on the bug. That's enough force to crush a fly, but not enough force to do anything to a train's windshield.

What force a fly or a train will exert on you is a different question. In either case, you get equal and opposite reactions, but the force of a train hitting you is, of course, much greater than the force of a fly hitting you.
posted by rossmik at 10:59 PM on August 24, 2008


92.5%
Fuck the damn clouds and the optical properties they rode in on...
posted by mystyk at 12:14 AM on August 25, 2008


45% In my defence, I did biology and chemistry for my Leaving Cert and I don't think most of this stuff was covered in the Junior Cert, or I'm stupid.
posted by minifigs at 1:09 AM on August 25, 2008


92.5%. Missed clouds, average velocity, and the engine question. I suspected I was wrong about the average velocity, because it sounded like a trick question, but it all depended on how you defined 'average'. Their version was average position over time: mine was average measurement over time. I believe they are, by definition, correct, so I'm not arguing, just explaining.

I didn't realize that clouds weren't water vapor, so I learned something. Thanks!
posted by Malor at 3:34 AM on August 25, 2008


92.5. Missed clouds, voltage being a unit thing and this cheater:

Energy is the ability to do work. In other words, if Ben needed 1000 joules of energy to move a box 5 meters across the floor it would make no difference whether he had 1000 joules of thermal energy or the same amount of mechanical energy. He could still do the work required to get the job done.

The first sentence is true. The rest is claimed to be a restatement of the first sentence.
posted by DU at 4:21 AM on August 25, 2008


Friction provides the force which "pushes" a car forward as it accelerates down the road.

Not if it has a jet engine.
posted by Enron Hubbard at 5:32 AM on August 25, 2008 [2 favorites]


30) An atom is just like a tiny solar system in which the nucleus is like the Sun and electrons are like tiny planets orbiting the nucleus in elliptical paths.

Oh for chrissake... no, of course it's not completely analogous, and there are discrete quanta of energy that determine orbital paths, and countless other deviations, but if you had to explain to someone on a whiteboard how the damn thing works, you would draw a l'il mini-solar-system.

I got an 82.5, with the heuristic 'if it sounds like it's a sneaky end-around to something simple, answer false.' Pedants.
posted by Mayor West at 5:32 AM on August 25, 2008


90%. The ex physics geek in me wants to say "you suck - start studying again." But really, I'm pretty proud that I remembered most of the foundational stuff from that long ago. Yay, brain! (Now...where did I put those books...)
posted by ThusSpakeZarathustra at 6:13 AM on August 25, 2008


rossmilk, your answer basically said, "they're exerting the same amount of force because they're exerting the same amount of force."

I guess my question is "how do things respond with an equal force"? I mean, if I hang a ball from a string, and I swing at it with a bat, and then a two year old swings at it with a whiffle bat, and then a professional baseball player hopped up on steroids swings at it with a metal bat, every time suddenly the ball is going to exert an equal force back on that bat. Oh, and every single time, even with my weak-ass swing, the ball is going to jump backwards. So despite its "equal" exertion of force it shoots way the heck back. I know, this is where momentum comes into play. I guess in my mind when I think "equal forces exerting" I can't get the metaphor of a tug-of-war out of my head. And obviously that is totally the wrong metaphor for Bug v Train.
posted by Deathalicious at 6:17 AM on August 25, 2008


When you swing softley at your tetherball, the contact between the ball and causes the bat to slow down (decelerate) a little bit, and the ball to accelerate a little. If you swing the bat hard, it'll slow down more when it hits the ball (in absolute terms), and the ball will shoot away faster. The deceleration of the bat multiplied by its mass is equal to the acceleration of the ball multiplied by its mass. F = m * a for both objects.

(which isn't much of an explanation, but it might make it a bit more clear what happens intuitively)

92.5 by the way, but only because they're wrong about the freezing/melting temperature of water. And because I couldn't remember if velocity was a vector.
posted by fvw at 6:44 AM on August 25, 2008


82.5. The question says unwanted heat transfer. If I want 0% heat transfer in my magic frictionless engine, I'm going to have fucking 0% heat transfer!

I don't understand the problems with the cloud question. Clouds just are liquid water and ice, not water vapor.
posted by afu at 7:14 AM on August 25, 2008


I consistently fucked up questions that had to do with vector vs scalar thinking. Otherwise, I got most of the questions right but my score was still not higher than the guy who just guessed "false" for every question.
posted by Electrius at 7:27 AM on August 25, 2008


87.5% - a couple of the kinematics questions really threw me (mainly because i have no clue what the formal definitions of velocity and acceleration are). also missed the shot-put question (because apparently newtonion physics is so radically new i haven't had time to assimilate it), the one about the direction of flow in a simple circuit, and the one about whether a milli-flibberty is equal to a cubic centi-whatchamadoodle.

not too shabby for an arts and sciences guy. i'll pass this along to my physics major coworker.
posted by saulgoodman at 7:29 AM on August 25, 2008


Deathalicious: I can't get the metaphor of a tug-of-war out of my head. And obviously that is totally the wrong metaphor for Bug v Train.

I'm afraid so. Tug-of-war teams have near-equal masses, bugs and trains do not.

Newton says that a force is equivalent to the product of mass and acceleration. Lets assume the bug is innocently hovering at train height above the track (stationary, relative to the ground), and the train approaches it at some speed. When the train hits the bug, the bug exerts a force on the train and the train exerts a force on the bug. These forces are equal in magnitude and in opposite directions. The bug pushes back on the train and the train pushes forward on the bug with equal force.

Because they have such radically different masses, the consequences for each are, of course, radically different. The bug is accelerated from zero to the the speed of the train near-instantaneously - a huge acceleration. But the bug's mass is very, very small so, despite the high acceleration, the opposing force applied to the train is very very small. Simultaneously, the train (theoretically*) decelerates a very, very small amount due to the action of the opposing force from the bug. The deceleration is very, very small because the train has such a huge mass compared to the bug. Equal and opposite forces, but very different masses, resulting in very different accelerations for each of the colliding bodies.

Now, if we replace the bug with you, we replace the bug with a body of much greater mass. You are still a mass that's very small compared to the train, but much bigger than the bug. When the train collides with you, the same principles apply, equally opposing forces. The acceleration you experience is close to that of the bug, but because your mass is much greater the force you experience is much greater. The result remains catastrophic for the object (you) hit by the train.

If we replace the train with you and you collide with the bug at similar speed, the force is small again, because the bug has such little mass.

* A real train is not an ideal rigid solid. Perhaps, more realistically, the force from the bug causes a tiny localized deflection in the windshield.
posted by normy at 8:38 AM on August 25, 2008 [1 favorite]


97.5% - Stupid clouds.


I think *unwanted* heat transfer is the key. The burning fuel still makes heat, which means an efficiency lost; it's just that the heat goes out with the exhaust gases instead of into the engine block. This means the engine can't be converting *all* the energy to motion; it still loses energy to heat.

I got it wrong, too.


The whole mess about the IC engines is them attempting to ask "Do you know about Carnot heat engines?" without mentioning Carnot heat engines. Stupid way to put it, yes, but they are trying to get at something more than "is this impossible?"
posted by Phineas Rhyne at 8:39 AM on August 25, 2008


29) A cloud's mass consists primarily of water vapor.
Explanation: false; blah blah gas vs. condensed vapor blah blah

Bzzzt! If clouds were mostly water (in any form) then jet engines wouldn't work in 'em. Obviously clouds are mostly air (hence mostly N2).
posted by ryanrs at 9:11 AM on August 25, 2008


Friction provides the force which "pushes" a car forward as it accelerates down the road.

Not if it has a jet engine.


And a... conveyor belt?
posted by FatherDagon at 10:03 AM on August 25, 2008


92.5%
posted by weapons-grade pandemonium at 11:24 AM on August 25, 2008


[...] the entire test is more about use of language than science..

Sorry, but I can't get on board with this. Science absolutely depends on the precise and accurate use of language (both natural and mathematical). So you're drawing a distinction that, in reality, isn't so distinct.
posted by Crabby Appleton at 11:51 AM on August 25, 2008


95%. On the ones I didn't know (in Electricity and Basic Kinematics), I guessed based on how "tricky" all the other questions were, so I actually should have received an 87.5%.
posted by effwerd at 12:35 PM on August 25, 2008


This is why I have a bachelor's in sociology and a master's in urban planning. 47.5%, and I randomly guessed on about 5 questions.
posted by desjardins at 1:26 PM on August 25, 2008


Interesting use of tricks here. They are, in many cases, quizzing vocabulary and not physics. For example, the lay definition of "velocity" is different from the technical one.
posted by Mo Nickels at 1:57 PM on August 25, 2008


It's not a trick! This is a physics test. "Velocity" has a precise definition in physics. It's a vector quantity.
posted by Crabby Appleton at 2:01 PM on August 25, 2008


Why would you expect to do well on a physics test by using the "lay" definitions of physics concepts? There's no non-technical version of physics. Physics is about as technical as it gets.
posted by Crabby Appleton at 2:05 PM on August 25, 2008


I got an 85%, but I was also multitasking while working.

I was a bit mad that I missed the one about the car wreck, the trees, and the seats propelling the passengers. The way it was worded sucked. My though process was, yes, they gained a bunch of momentum because the seats exerted a force on them while the car was accelerating.

And I missed the stupid cloud one too.

I'm actually proud that I did this well, considering I haven't touched this stuff for 10 years.
posted by jeffamaphone at 3:03 PM on August 25, 2008


97.5%, bizzies. I have a degree in chem, but have been a software developer for nearly nine years now, so I'm pleased that I haven't gotten too rusty. The only one I missed was the voltage vs. force one, and I acknowlege that I missed it fair and square--my intuition told me there was something wrong with the wording, but I couldn't identify what it was in concrete terms.
posted by oats at 3:23 PM on August 25, 2008


If Shandra was driving around a circular track, wouldn't her average velocity by 12π radians / second?
posted by peeedro at 9:33 PM on August 25, 2008


or more likely be 12π radians / hour
posted by peeedro at 9:35 PM on August 25, 2008


Not sure if you're being serious peeedro, but on the off chance you are.. Nope, that is "angular velocity", different vector from "velocity". So, it comes down to the same precise use of language that permeates the rest of the test.
I hate the way π renders in the MetaFilter font.. I wonder if I should request a pony :P
posted by Chuckles at 12:14 AM on August 26, 2008


Hooray, I'm 90% savvy. Then again, I used to be a physics major, so I should have gotten 100%. That engine efficiency question kind of pissed me off too, chimaera. If we're already ignoring most of the principles governing mechanical motion, why am I supposed to immediately think of the (much more complex and easier to leave out) laws of thermodynamics?
posted by tehloki at 1:43 AM on August 26, 2008


I hate the way π renders in the MetaFilter font.. I wonder if I should request a pony :P

One option is
<tt>π</tt>
which produces π. But you're right, the way it renders in something like Times is much more pleasant.

Fishing through the Unicode charts there's also ℼ (&​#x213C;) but I don't know how many people that would show up properly for.
posted by XMLicious at 7:42 AM on August 26, 2008


π - Hmm, I didn't know about the <tt> tag, or at least I forgot about it. Still, a bit small.

The unicode showed up as something quite odd. Oh, actually not so odd.. 21 over 3C with a box around it. Heh..
posted by Chuckles at 9:45 AM on August 26, 2008


It looks like this to me, because I have a font installed that includes that glyph.
posted by XMLicious at 10:26 AM on August 26, 2008


normy -- I was just doing a lot of thinking, and I think my problem is that I have a huge problem separating momentum from force. Abstractly, I understand that the two are not really related...p=mv vs F=ma, the only shared variable is mass.

I'm imagining a scenario where instead of a mosquito, there is a boy (poor fellow!) tossing a ball up into the air. A train arrives, smashing into both the boy and the ball. Now, the (boy+ball) exerts the same amount of force on the train as the train exerts on (boy+ball), and the boy exerts the same amount of force on the train as it exerts on the boy, same for the ball. Which I guess means that these forces are all different...so there is not one constant amount of force that a train hitting "something" exerts...that would be momentum instead, which was why I was confused a bit...so the reason that the mosquito can exert the same amount of force on the train as the train exerts on it is partially because that force is proportional to the masses of the things exerting the forces...correct? Although that has me a bit confused, because I'm guessing that the boy is certainly going to accelerate away from the train at a slower rate than the ball, right? And, if so, if
mboy > mball
and
aboy < aball
then fiddle-dee carry the one
Ftrain+boy/mboy≠Ftrain+ball/mball
so they're not directly proportional.

Anyone want to help a village idiot out here?
posted by Deathalicious at 12:52 PM on August 26, 2008


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