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jerflast Tuesday at 1:57 PM45 repliesview on HN

One of my Core Memories when it comes to science, science education, and education in general was in my high school physics class, where we had to do an experiment to determine the gravitational acceleration of Earth. This was done via the following mechanism: Roll a ball off of a standard classroom table. Use a 1990s wristwatch's stopwatch mechanism to start the clock when the ball rolls of the table. Stop the stopwatch when the ball hits the floor.

Anyone who has ever had a wristwatch of similar tech should know how hard it is to get anything like precision out of those things. It's a millimeter sized button with a millimeter depth of press and could easily need half a second of jabbing at it to get it to trigger. It's for measuring your mile times in minutes, not fractions of a second fall times.

Naturally, our data was total, utter crap. Any sensible analysis would have error bars that, if you treat the problem linearly, would have put 0 and negative numbers within our error bars. I dutifully crunched the numbers and determined that the gravitational constant was something like 6.8m/s^2 and turned it in.

Naturally, I got a failing grade, because that's not particularly close, and no matter how many times you are solemnly assured otherwise, you are never graded on whether you did your best and honestly report what you observe. From grade school on, you are graded on whether or not the grading authority likes the results you got. You might hope that there comes some point in your career where that stops being the case, but as near as I can tell, it literally never does. Right on up to professorships, this is how science really works.

The lesson is taught early and often. It often sort of baffles me when other people are baffled at how often this happens in science, because it more-or-less always happens. Science proceeds despite this, not because of it.

(But jerf, my teacher... Yes, you had a wonderful teacher who didn't only give you an A for the equivalent but called you out in class for your honesty and I dunno, flunked everyone who claimed they got the supposed "correct" answer to three significant digits because that was impossible. There are a few shining lights in the field and I would never dream of denying that. Now tell me how that idealism worked for you going forward the next several years.)


Replies

don-codelast Tuesday at 3:53 PM

This is, more or less, exactly what happened when I took Electronics I in college.

The course was structured in such a way that you could not move on to the next lab assignment until you completed the one before it. You could complete the lab assignments at your own pace. If you failed the lab, you failed the class, regardless of your grade.

The second or third lab had us characterize the response of a transistor in a DIP-8 package, which was provided to us. If you blew it up, you got a slap on the wrist. That DIP-8 was otherwise yours for the class.

I could _never_ get anything resembling linear output out of my transistor. The lab tech was unhelpful, insisting that it must be something with how I had it wired, encouraging me to re-draw my schematic, check my wires, and so on. It could _never_ be the equipment's fault.

Eight (!) weeks into that ten week class, I found the problem: the DIP was not, in fact, just a transistor. It was a 555 timer that had somehow been mixed in with the transistors.

I went and showed the lab technician. He gave me another one. At this point, I had two weeks to complete eight weeks of lab work, which was borderline impossible. So I made an appointment to see the professor, and his suggestion to me was to drop the class and take it again. Which, of course, would've affected my graduation date.

I chose to take a horrible but passing grade in the lab, finished the class with a C- (which was unusual for me), and went on to pretend that the whole thing never happened.

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npongratzlast Tuesday at 2:42 PM

> From grade school on, you are graded on whether or not the grading authority likes the results you got.

I took an exam in a high school science class where I answered a question with the textbook's definition exactly as presented in the textbook, complete with the page number the definition was found on. I knew a bit about the topic, so I then cited outside scientific sources that explained why the definition was incomplete. There wasn't enough room to complete my answer in the space provided, so I spiraled it out into the margins of the exam paper.

My teacher marked my answer wrong. Then crossed that out and marked it correct. Then crossed that out, and finally marked it wrong again. During parent-teacher conferences, the science teacher admitted that even though I answered the question with the exactly correct definition, my further exposition made him "mad" (his word), and because he was angry, he marked it wrong.

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interroboinklast Tuesday at 4:08 PM

> Right on up to professorships, this is how science really works.

Reminds me of Feynman's "Cargo Cult Science" essay[1]

    One example: Millikan measured the charge on an electron by an experiment
    with falling oil drops and got an answer which we now know not to be
    quite right.  It’s a little bit off, because he had the incorrect value
    for the viscosity of air.  It’s interesting to look at the history
    of measurements of the charge of the electron, after Millikan.  If you
    plot them as a function of time, you find that one is a little bigger
    than Millikan’s, and the next one’s a little bit bigger than that,
    and the next one’s a little bit bigger than that, until finally they
    settle down to a number which is higher.
    
    Why didn’t they discover that the new number was higher right away?
    It’s a thing that scientists are ashamed of—this history—because
    it’s apparent that people did things like this: When they got a number
    that was too high above Millikan’s, they thought something must be
    wrong—and they would look for and find a reason why something might be
    wrong.  When they got a number closer to Millikan’s value they didn’t
    look so hard.  And so they eliminated the numbers that were too far off,
    and did other things like that.  We’ve learned those tricks nowadays,
    and now we don’t have that kind of a disease.
Yeah, not sure I'm 100% agreed on that last statement (:

[1] https://calteches.library.caltech.edu/51/2/CargoCult.htm

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veggierolllast Tuesday at 2:48 PM

I can totally relate. I had the same experience in grade school science class, where the teacher assigned an experiment with a suggested solution and an invitation to come up with your own method.

I was the only person in class that chose to do my own method. And, it didn't work because I didn't account for an environmental difference between my house and the school classroom. And, he gave me a failing grade.

It really killed my interest in physics for a long time. I focused on biology from then through college.

Ultimately, the problem was that he didn't make clear that the only thing that we were being graded on was accuracy, not experimental methods or precision. (My solution was precise, but inaccurate; whereas the standard solution was accurate but imprecise) Also, it's possible everyone else in class knew the culture of the school, and I didn't because it was my first year there. So, I didn't realize that they didn't value creativity in the way I was used to.

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Sesse__last Tuesday at 4:12 PM

My physics professor told us once about a lab he had to do when he was a student himself, about measuring the adiabatic gas constant of air. The workload at that point was immense, so lots of students would just write a report and give the textbook answer—and be marked wrong.

It turned out the TA had sabotaged the experiment by putting alcohol in the bottom of the (dark glass) measurement bottle, so the measurement would be of the constant of “air with a fair amount of alcohol vapor in it”, which would give a different constant. And if you actually did the exercise, you'd get that “wrong” number, and that would be the only way to get the lab approved.

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joshstrangelast Tuesday at 5:44 PM

> you are never graded on whether you did your best and honestly report what you observe. From grade school on, you are graded on whether or not the grading authority likes the results you got. You might hope that there comes some point in your career where that stops being the case, but as near as I can tell, it literally never does. Right on up to professorships, this is how science really works.

This, so much this. I disliked any lab work in my science classes (in HS/College) for this exact reason. I can't tell you how many numbers I fudged because I wasn't getting the "right" results and there was no time/appetite/interest in figuring out why it was wrong, my options were lie and get a good grade or report what I saw and get a bad grade.

And yes, in college specifically, the equipment we were working was rough. There was so much of "let's ask the other 2 groups near us and we will all shave our numbers a bit to match/make sense".

cycomaniclast Tuesday at 6:37 PM

On the other hand my experience as both a graduate and professor teaching students are equally discouraging.

1. Most students don't want to have to think. As a student I was always annoyed that we'd be given exact instructions with an exactly know result to reproduce, while this is generally not how real experiments work. So when I designed an experiment I wrote instructions that reflected more the real life experience, I.e. instead of "place the lens A 10mm from object B" it was "place the lens one focal length away from the object, to know the focal length of your lens you can use a light source at Infinity (far away)." after I left my university the instructions were reverted back because students complained that they didn't get step by step instructions.

2. Students dutifully write down a measurements that is of several orders of magnitude with absolutely no acknowledgement/discussion. I have seen speed of light barely faster than a car and mass of a small piece material in 100s of kg (usually because students forget a nano or giga in a calculation), without any discussion that the result is nonsensical.

3. Similar they make a fit like the one in the OP and don't even discuss the error bars. Or (and that's already the better students) they make a fit with tiny error bars, but get the wrong result (typically due to some mistake like above) and in the discussion say the difference to an expected error is due to measurement error.

Now I also know that there are crappy graduate students who teach because they are teaching the "only get the correct result" but it's often very difficult to improve teaching because students will immediately complain that they have to adjust to changes.

thelaxiankeylast Tuesday at 9:27 PM

'flunked everyone who claimed they got the supposed "correct" answer to three significant digits because that was impossible.' while I've never seen anyone flunked for this, I certainly have taken off substantial amounts of points, and seen others do the same, for 3 significant figures when 2 is the absolute highest reasonably possible (and realistically, one sig fig was what we actually wanted).

I've run the exact lab you're describing, and I think we gave full credit for anything between 5m/s^2 and 20 m/s^2 provided there was some acknowledgement that this was at odds with what was expected. We very often would check in halfway through class and either tell the kids what they were doing wrong, or even tell them to write something 'this is at odds with literally all known science and I think I don't trust this'. For this particular lab, I've never seen errors as large as the ones you've described, so your lab was likely very poorly set up.

In other cases, I've made extra time (and allow students to come in) in case their numbers were so weird as to be problematic; just depends on the lab. Any teacher worth their salt will do this. It's a shame the teachers you had were terrible and incentivized bad stuff.

If being in a lab has taught me anything, it's that doing good science is often morally difficult. Sticking by your guns is hard.

But you are right in some sense: there are definitely incentives to... misreport. The best we can do as teachers is to reduce those as much as possible and reward kids/students for being honest.

hydrogen7800last Tuesday at 2:17 PM

>Roll a ball off of a standard classroom table. Use a 1990s wristwatch's stopwatch mechanism to start the clock when the ball rolls of the table. Stop the stopwatch when the ball hits the floor.

Our class had some kind of device that would either punch a hole, or make a mark on paper at a regular time interval. We attached a narrow strip of paper to the ball, and let it pull through the marking device as it fell from the bench to the floor. We then measured the distance between each mark, noting that the distance increased with each interval, using this to calculate g. I don't recall anything more than that, or how I did on that lab. I received a 50 one marking period for lack of handing in labs, but had a 90+ average otherwise in the class.

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wavemodelast Tuesday at 3:10 PM

The worst is college science classes where sometimes the provided equipment and/or procedures aren't even correct, and the professor isn't around and you're dealing with a TA who is just as confused as you are.

So you debate with yourself between writing down the effect you got (and trusting that you will be rewarded for integrity and effort and rigor), or simply writing down what you know the effect was supposed to be.

Most people (smartly) do the latter.

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bee_riderlast Tuesday at 2:37 PM

That’s pretty bad. On top of being unfair, it was a total missed opportunity to talk about the law of large numbers (I wonder if they could get a decent sample by combining everybody’s measurements) or skew (maybe everybody is a couple milliseconds too low just based on reaction time).

Or there could be some air resistance if you used, like, ping-pong balls.

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snailmailmanlast Tuesday at 5:56 PM

I had a physics class in my high school. 2014? 2015? Around then.

The teacher had us using a stopwatch on our phones. We would repeat the experiment several times and average the result, because manually doing a stopwatch was terrible- multiple samples kinda helped.

My group figured out we could get things way more accurate if we videoed the experiment in slow-motion with a phone, keeping a digital stopwatch in frame. It took an extra step of math, subtracting out the start time, but in slow motion we could be accurate to 1/120th of a second. Our results were easily the most precise in the class. Equipment can make a huge difference, and slow motion video was considerably more accurate than “Mike trying to time it right”

finnthehumanlast Tuesday at 5:13 PM

>The lesson is taught early and often. It often sort of baffles me when other people are baffled at how often this happens in science,

Math and some sciences have the aura of definitive right and wrong, so even though by college everyone knows the expression "give the answer the teacher wants to hear", they just think in those subjects the teacher has access to absolute answers.

The primary thing taught by our schooling system (and 2nd place isn't even close) is bureaucracy obedience. This has the obvious effects, but one of the subtler ones is deference to "science" as an authority requiring obedience rather than the process of figuring shit out.

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analog31last Tuesday at 10:46 PM

I'm certainly not going to defend your teacher or your experience, especially at the high school level. That's too soon. And I also remember being indignant for a similar experience in analytical chemistry.

But... there's a point in one's development as a science student, where science becomes more nuanced than "doing your best and honestly reporting what you observe." Those things will always be there of course. But in an experimental science, doing an experiment and getting accurate results is a vital skill, or you'll never make progress.

Naturally you have no standard for checking a measurement whose result is truly unknown, but you can insert the equivalent of breakpoints where you make sure that the same data do reproduce known results. Ironically for the discussion here, those are called "gravity tests." Students need to know at some point if they're going to like the experimental side of science. Getting things right is part of it. Some people don't belong in the lab.

I happen to be stuck at the "gravity test" level in my day job. My experiment produced a calibration that's reproducible, and that I could use, but it doesn't make sense. I'm not going to move forward until it does.

The problem with a lot of teaching is that the purpose of the lesson is never explained, and the nuanced view is never spelled out.

amy214last Wednesday at 3:07 AM

The same thing happens in organic chemistry. You're graded by your yield. If you put 10 units of A in, cooked up 9.9 units of product B, great job! But if it's 0.01 units, good luck, or 0, heaven save you. of course, they might give you 15 units of A to begin with, you're only to use 10. So at the end of it, you get 9.9 out out of 15 in, and say you only put 10 in. Of course, if you get 14 units of product out of "10" in, you just cut down the product accordingly. I'm pretty sure with organic chemistry lab being a core pre-med course, that this might be more the norm than the exception.

jessekvlast Tuesday at 6:00 PM

In the first grade I knew exactly where on my fingers the width was an inch or a cm.

I got called up in front of class and punished for cheating on a length estimation assignment.

They told everyone I was a cheater that used a ruler :P

Besides contributing to the sob stories, my point is maybe some of those kids got lucky with a good measurement/timer. Sorry you had a really bad teacher.

Lerclast Tuesday at 5:19 PM

I had a similar experience measuring gravity in high school. Our method was using a ticker timer.

One of these. https://www.physicsforums.com/threads/the-history-of-ticker-...

The inevitable happened, after the years of classroom abuse the timer provided enough friction that the falling object swung on the paper like a pendulum and slowly made its way to the ground over the course of about 5 seconds.

We analysed the meaningless dots on the paper and wrote up a calculation of gravity of 9.6m/s^2 attributing the 0.2ish to 'possible friction or accuracy of the timer'

This taught me more about science than I care to think about.

BeetleBlast Tuesday at 3:42 PM

That's a poor way to measure g. In multiple schools I went to, the standard was to measure g via a pendulum (I think measuring the period).

I measured a 9.86[1] :-) Mostly dumb luck. But most people in the class would get decently close (9-10.5).

[1] The correct value is closer to 9.81.

charlieyu1last Tuesday at 5:08 PM

I used to teach math to 5th graders about angles. I let them draw a triangle and measure the angles with a protractor, then calculate the sum. The sum is usually around 177 or 178 degrees.

TeMPOraLlast Tuesday at 7:06 PM

> no matter how many times you are solemnly assured otherwise, you are never graded on whether you did your best and honestly report what you observe. From grade school on, you are graded on whether or not the grading authority likes the results you got.

Wouldnt've helped me before late high school, but that "whether or not the grading authority likes the results you got" part cuts both ways. That is, if you put some extra effort into presentation, you can get at least some of authorities to recognize your effort. Or, if you're really good, you can even bullshit wrong results past them, as long as you give a strong impression of competence.

Or at least that's what undergrad studies taught me; for random reason I went into overkill for some assignments, and I quickly discovered this worked regardless of the validity of my results.

I guess a big part of it is that most other people a) don't really put in much effort, and b) don't see any importance of the work in larger context. So I found that if I showed (or faked) either, I was set; show both, even better.

(Though it didn't work 100% well. I distinctly remember spending a lot of time figuring out how to simulate lexical scope and lambdas with strings & eval in Lotus notes. My professor was impressed, even suggesting I write the details up, but then she proceeded to fail me on the exercise anyway, because I didn't actually do half of the boring things I was supposed to.)

(It also taught me to recognize when someone else's deploying smokescreens of competence to pass lazy or bad results.)

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Tistronlast Wednesday at 7:11 AM

I remember in chemistry class in high school (in Sweden), where we'd do lab work in pairs often. I'd pair up with the other actually smart and interested guy in class and we'd divide the work between us: One of us would start doing the theoretical work, calculating what numbers we should be getting, and the other would do the experiment. Then we'd adjust all our findings to be within what was theoretically reasonable.

We got good grades.

Is it like 5 people doing real science and everybody copying their homework? I mean, we've got technology to prove that a lot of natural science must be right in some way, so somebody is doing real discovery and real experiments. Right?

andrubylast Wednesday at 9:37 AM

Out of curiosity, could you add which country you are from? I think in general there's similarities everywhere.

In Belgium (Gent to be more specific) where I'm from, there is a high cultural degree of critical thinking, and if I handed in a report like that, with the accompanying numbers, our teacher would not have given it a failing grade. Especially if the report was accompanied with either a written or verbal disclaimer mentioning the limitations of the measuring equipment and that the results didn't match your expectations.

grishkalast Tuesday at 4:22 PM

In my university we had a more precise setup for that. It was some sort of weight on a rail at a known incline, and a digital timer with two sensors known distance apart that start and stop it.

Yet in my class we still had results as low as 7 and as high as 12. We all got passing grades. But the protocol for these lab assignments was always such that you had to have your "measurements sheet" signed by the professor, and you turned it in with your report later.

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RunSetlast Tuesday at 11:53 PM

The story of Isaac Asimov's "shotgun curve" is relevant:

https://archive.org/details/Fantasy_Science_Fiction_v056n06_...

billtilast Tuesday at 3:25 PM

Having recently gotten into quantum and listening to a lot of audiobooks on the history of it, that’s one of biggest takeaways for me. So many major advances in theory that languished for years because of the politics of the day of the personal opinions of their advisor, only for a physicist with greater standing to rediscover the same thing later and finally get it some attention. (Hugh Everett and David Bohm being two examples)

sobriquet9last Tuesday at 2:07 PM

I think if you showed not only the point estimate, but also some measure of uncertainty like standard deviation, it should have given you a passing grade. It's hard to say why an answer like 6.8 +- 5 is wrong.

Even if you don't yet have formal statistical chops, it should be at least possible to show cumulative distribution function of results that will convey the story better than a single answer with overly optimistic implied precision.

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kkylinlast Tuesday at 6:13 PM

For typical distances (say the height of a table or a shelf) the time should be on the order of a fraction of a second. There's a couple hundred ms delay in the human auditory + motor system, which is a sizable fration of the time you're trying to measure and one would have to try to account for (but not all that easy, especially for a HS physics class).

ryukopostinglast Wednesday at 12:12 PM

My teacher had a different solution to this exact problem. He ran the same test, but had us run it in the school's atrium, where we could drop objects a good 30 feet to the ground. It was a long enough drop that the stopwatches weren't as much of a hindrance. We destroyed a floor tile, but other than that, it went well to my recollection.

svennidallast Wednesday at 9:43 AM

I had a teacher in college who before teaching, worked for a company within the gambling industry. He then went on to start his own company, which was as I heard, based purely on the knowledge and connections he made at his former employer. Dude struck gold getting rich off of gambling addicts. Due to his financial success, he thought of himself as some kind of Steve Jobs and an expert on all things related to tech. He would claim to have predicted the popularity of many tech related things, e.g. cloud solutions like google drive and google docs. Problem is that his predictions all came long after all these things had become mainstream.

His lectures were full of incorrect facts. He would ask the class questions and give us wrong answers. I’ve never seen a man so confidently incorrect.

He wrote a book about the fourth industrial revolution in which he used the introduction to brag about all the places he used for writing his book. Including his home in a upper class neighborhood, his home abroad, cafes around the world, etc. His book also contained errors that a simple google search would’ve helped him correct.

A lot of the stuff he taught were interesting. But all the contents of the course could’ve been covered in a video or two.

In my final paper I wrote about how the popularity of new tech can regress even though the tech gets up to great quality. He had stated that you wouldn’t see a computer science student using a laptop after 5 years (this was 10 years ago). They would all be programming on their ipads because the touch screens had become so good. As well as how everyone in their fields were replacing their interfaces with touch screens. I wrote about how mechanical keyboards and physical midi controllers had never been as popular in many fields like audio and video production.

Needless to say. I failed the class. I was just supposed to regurgitate his blogs and opinions.

This was not the only thing to make me lose most all my confidence in any higher education at a time. I went from critical thinking to skeptical thinking. And it was not solely because of my opinions about this teacher. It was because of the opinions of his peers and in how high regard he was kept in the academic society.

I learned that schools are not institutions of science. They’re more like a Church of Science or at the very best, Science’s weird fan club with a weird internal popularity power struggle.

Edit: A word.

stanford_labratlast Tuesday at 5:24 PM

> Right on up to professorships, this is how science really works.

Why I am making my exit from academia and research entirely as soon as I finish my PhD. The system is filled with wonderful, intelligent people but sadly simultaneously rotten to the core. It in fact, did not get better as I moved from undergrad to grad school.

eitlandlast Tuesday at 5:23 PM

Brings back memories!

In my case it was a slide on an air cushioned aluminum beam.

And the interesting part was that for some reason, if we pulled it up towards the top, behind some point it used shorter time to travel across the whole beam.

I put quite some effort into figuring out why, repeating it again and again, studied the beam to see if there was any irregularities, brainstormed on why this happened.

My physics teacher really liked that at least some of his students had dug into it (I think we weren't the only group) and made it very clear in the feedback (he did not mention who had gotten it wrong, just that some had observed this and looked into it instead of covering it up or throwing away the data we didn't like).

Didn't exactly enjoy school, but people like him made it a lot better.

matheusmoreiralast Tuesday at 3:11 PM

https://v.cx/2010/04/feynman-brazil-education

> Then I held up the elementary physics textbook they were using.

> There are no experimental results mentioned anywhere in this book, except in one place where there is a ball, rolling down an inclined plane, in which it says how far the ball got after one second, two seconds, three seconds, and so on.

> The numbers have ‘errors’ in them – that is, if you look at them, you think you’re looking at experimental results, because the numbers are a little above, or a little below, the theoretical values. The book even talks about having to correct the experimental errors – very fine.

> The trouble is, when you calculate the value of the acceleration constant from these values, you get the right answer.

> But a ball rolling down an inclined plane, if it is actually done, has an inertia to get it to turn, and will, if you do the experiment, produce five-sevenths of the right answer, because of the extra energy needed to go into the rotation of the ball.

> Therefore this single example of experimental ‘results’ is obtained from a fake experiment.

> Nobody had rolled such a ball, or they would never have gotten those results!

Reading your post, I now realize education is dysfunctional in the entire world, not just in my country. Small comfort.

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sciencejerklast Tuesday at 4:39 PM

I got a D in a highschool Biology Genetics Lab working with Fruit Flies because our Chi Squared p-value was a little less than the common significance value of 0.05.

Our results were close enough that we could still easily determine the phenotype and genotype of the parent and grandparent Fruit Flies (red/black eyes), but it was kind of a bummer to be punished in a highly error prone experiment (flies dying from too much ether, flies flying away, flies getting stuck in food and dying, etc).

It did teach me to be more careful when running experiments but I probably would have given myself a C, not a D

ahartmetzlast Tuesday at 5:30 PM

When I did the mandatory lab exercises in physics, there was a more benign variant of that problem: the conventional value had to fall inside the error interval. However, it was allowed to add additional errors with a good explanation (...some creativity). I really didn't like to increase the estimated errors to make the result work, and I think the (unimportant) grades were reduced for doing it.

I remember being really consistent with the stopwatch in one exercise, so sadly the spread of measurements (implying a natural uncertainty) was small. That was bad!

YeahThisIsMelast Wednesday at 8:08 AM

This is the complete opposite of my experience.

You always got partial credit even if you made a mistake as long as the following results were achieved using the correct method and with the correct calculations despite one of the inputs being wrong due to a previous error.

planklast Tuesday at 8:32 PM

Have a complete different experience. As a physical major, did a famous Millikan's oil drop experiment. Am a terrible experimentalist (went on to do my PhD in theoretical physics), so we got a charge of about 1/3 of the charge of an electron. Now, as I did not get a Nobel prize, I did not actually measure the charge of a single quark, but still got good enough grades for this study.

emmelaichlast Tuesday at 5:10 PM

I had a similar experience in Physics 101 and Chemistry 101. The labs were chaotic and had limited time. If you were even a little bit unlucky it would be impossible to even finish them let alone get remotely decent results.

I'm convinced 60% of the class faked results or copied many results from previous year's students.

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m463last Tuesday at 11:37 PM

When we did that in high school, we took long exposure photos with a strobe light and measured where the ball was at each strobe interval. I think it worked out well.

I'm sure nowadays the experiment would just be one slow-mo video on your phone.

zvoryginlast Tuesday at 8:20 PM

In my high school, without naming any names, the teacher told us all that anyone who changed their results to 9.81m/s^2 was doing science incorrectly. And we were graded on our analysis of the experimental procedure, or something like that.

huijzerlast Tuesday at 3:16 PM

> The lesson is taught early and often. It often sort of baffles me when other people are baffled at how often this happens in science, because it more-or-less always happens. Science proceeds despite this, not because of it.

I think we should definitely not learn from this that science still works despite those things. Because then it's easy to just say it is what it is. I think it's much more helpful to be critical of the scientific process (scientific policies in particular) and see how it can be improved. As I said many times before here on Hacker News, basically nothing in science has changed since papers like Why Most Published Research Findings Are False by Ioannidis have come out. I think we as civilians should demand more from science than a bunch of false papers behind paywalls.

torginuslast Tuesday at 8:03 PM

On a side note, one thing every single one of my peers who have pursued a creative degree have echoed, be it architecture, literature, graphic design, industial design etc. - is that the only way to get a good grade is to find out what your professors personal preferences and opinions are and be in total and utter agreement with them.

Any amount of critical views tends to result in your work torn to pieces and you getting a shitty grade.

Your architecture professor likes turrets? Then better put them even on the chicken coop - that way he'll no you're one of the students who gets it.

Your lit professor loves a certain philosopher? - better not point out that you find his arguments circular, ponderous and betraying a lack of broad perspective.

This has been utterly weird to me considering I have encountered way less (but not zero) of this thing in engineering, and art is supposed to be about developing your self-expression, but I've heard this criticism so many times from so many places and formulated so strongly. I've had many people flat out leave their educations because of this, with others just quietly powering through.

This in of itself has changed my view of art education, and I've told many people to stay away from these places not because of the usual 'it's useless and you'll starve to death arguments' but because of this.

pshirshovlast Wednesday at 12:00 AM

Did the same. Least squares got me to 9.7

dkarllast Tuesday at 5:50 PM

At my high school, somehow physics was the dumb jock science course. I think it was because the head football coach taught physics for decades before retiring my sophomore year. Anyway, as a kid who was doing well in school and was headed for college, it was a natural decision for me to not bother taking physics and study for the AP test on my own. But one day a kid showed up in one of my classes with a hall pass for me to go to the physics classroom. The new teacher needed my help.

She had planned on teaching a lab on gravity and acceleration that day, but she was having trouble getting the right experimental results. Now, this story is not going to reflect well on her, so I want to say up front that she was already taking physics education at my high school to unprecedented heights by 1) trying out the lab on her own before trying to teach it, and 2) actually giving a shit about the results. I doubt the coach who had previously taught physics ever bothered to do any of the experiments himself, and I'm guessing everyone who ever turned in a lab report to him got an A regardless of the contents.

So there I am, a future physics major walking into a physics classroom for the first time in my academic career. I'm nervous because I have a reputation as a smart kid, and specifically as a smart science and math kid, but I was better with math and theory than with machines and measurements. I'm excited about getting to look smart in front of the other kids, but I'm also sweating bullets that there might be something about the equipment that I might not be able to figure out. So I ask her to show me what the experiment is and how she's doing it.

The experimental setup is a small but heavy piece of metal attached to a long, thin strip of the kind of paper used for carbon copies. (Or carbonless copies maybe. You know the paper where you write on one sheet, and there's a pressure-sensitive sheet underneath that creates a copy? It was a long strip of that pressure-sensitive paper.) The final piece of the experimental setup was a loud clacking thing that the strip of paper fed through. When it was turned on, a little hammer inside it slammed down every 1/4 of a second. The idea was, as the paper traveled through, the hammer left a mark every 1/4 of a second, and you could measure how far the paper traveled in each interval between the hammer strikes. Much more precise than a stopwatch!

You have already figured out how the experiment works. You hold the clacker at a fixed height against the wall or some other high fixed point, thread the weight end of the paper through it, turn the clacker on, drop the weight, and the clacker leaves marks on the paper that let you calculate g.

The teacher understood this, to an extent. But she decided that it would be less of a logistical hassle if the students did the experiment at their lab tables, by holding the clacker on the table and pulling the weight horizontally across the table with their hand. She tried this quite a few times herself, plotted the numbers, and could not get the plot to look like a parabola like in the textbook. I explained to her, "We're measuring gravity, so gravity has to do the work. If we move it with our hands, we're just measuring our hands. If gravity moves it, we'll measure gravity." We tried it, it worked, and she sent me back to whatever class I had been in when she sent for me.

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WhitneyLandlast Tuesday at 2:40 PM

So did you let this go without protest? Why not escalate it if it was clearly so unreasonable?

Sounds like there was more nuance to the story.

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