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Electron band structure in germanium, my ass (2001)

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Re: Electron band structure in germanium, my ass (2001)

#321

Post by fn-mote »

freedomben wrote: post #283
ethbr1 wrote: post #249

Earlier quoted context omitted.

The flip side of this is from the professor's perspective: some undergrad in every class will lie their ass off about why their assignment was delayed. Unfortunately, this reality produces no good options if you think someone is telling the truth: (1) make an exception, and be unfair to the rest of the class or (2) don't make an exception, and perpetuate unfairness for the impacted student.

That's fair, but in this case it should be pretty easy to verify if the person is lying. The claim is highly reproducible and the instructor wouldn't even have to do it.

It's only "reproducible" if you find other 555's mixed in the shipment but not distributed to students. Depending on what the error rate in the shipment packing is, that might be very easy or it might be quite hard. At any rate, it's a stats problem that the professor is unlikely to want to engage with. Unfortunately.

For the next semester, a good prof would have a QA step or a harnass that turns on a green light if you plug in a working-as-expected package. I can see how the lab assistant job gets plenty to do in a well-run course, and also how unlikely it is to be happening in real life. There aren't enough incentives.

Re: Electron band structure in germanium, my ass (2001)

#322

Post by fn-mote »

BeFlatXIII wrote: post #313
ethbr1 wrote: post #249

Earlier quoted context omitted.

The flip side of this is from the professor's perspective: some undergrad in every class will lie their ass off about why their assignment was delayed. Unfortunately, this reality produces no good options if you think someone is telling the truth: (1) make an exception, and be unfair to the rest of the class or (2) don't make an exception, and perpetuate unfairness for the impacted student.

Unfairness to the class, if kept under wraps, is a case of no one actually being harmed.

Translation: scammers get the green light.

Re: Electron band structure in germanium, my ass (2001)

#323

Post by opello »

anyfoo wrote: post #309
don-code wrote: post #118

Earlier quoted context omitted.

It's a good question! I didn't think to check the markings on the chip. The lab tech was convinced I was doing something wrong with my setup, and likewise he had me convinced it must be something wrong with my setup. Coincidentally, I've been knee-deep in some problems that I've applied the Cynefin framework to. I'd call this problem "chaotic", where throwing things at the wall might be _more_ effective than working…

No offense, but... when I was reading your story, I was somehow at least assuming that the marking on the part was somewhat unreadable or something... After getting befuddling answers, would it not have been natural to check the base assumptions, starting with do I have the correct part ? That is true as much in the "real engineering" world, as in school. You say "It could _never_ be the equipment's fault" as if it w…

Or even more likely in a lab setting: have another student test your part in their setup for A/B validation testing.

Re: Electron band structure in germanium, my ass (2001)

#324

Post by somat »

don-code wrote: post #245
michaelsbradley wrote: post #174

Earlier quoted context omitted.

I was in honors freshman chemistry at university. Tough class, all homework (lots of it) graded rigorously, but only the midterm and final counted toward the course grade. So if you wanted an A you had to get an A on both exams. After midterm, during every other lecture at least, the professor would sound a refrain: “An orbital is not a house! An electron does not live in a house!” Final exam had a small number of co…

I agree this seems overly principled to me. I recall a DSP class where there was an exam with a question like (not exactly this): > What does the following code print? > `printf("Hello, world!");` If you responded with: > Hello, world! ...which - of course - the whole class did, you got the question wrong. If you responded with: > "Hello, world!" ...which is actually not what that would print, you got the question ri…

Yeah that sucks, the hard life lesson where you have to swallow your pride and go "fine, I will put quotes on the infernal thing"

But... it does not print a string, a string goes into it but what comes out of the function is not that programmatic feature we call a string in any way shape or form, what comes out depends on the output device specified, it may be ink on paper, lit phosphors, or a stream of bytes. none of which can you use in your program as a string.

sprintf being a notable exception of course. there you do get a string out of it.

Update: language is weird and the more I read my statement the weirder it gets, all I can do is add this cryptic note. "When you print a string it does not produce a string", this usually means I am wrong about something.

Re: Electron band structure in germanium, my ass (2001)

#325

Post by Baeocystin »

mook wrote: post #279
gopher_space wrote: post #231

Earlier quoted context omitted.

“Is the box plugged in? Did you cycle the power?” I’ll trust that you understand each of those words individually but later verify that the box is actually plugged in.

That's why tech support has moved on to "unplug the thing, wait a minute, then plug it back in". It gives the capacitors to discharge; but more importantly, it gives an excuse to actually force the person to plug the thing in.

I ask people to unplug their Ethernet cable and tell me the colors they see on the wires all the time.

I don't care, of course. But they'll happily do that, where if I ask them to verify if the cable is properly plugged in, 99% of them will just say yes without so much as glancing in the cables' direction.

Re: Electron band structure in germanium, my ass (2001)

#326

Post by dosman33 »

orlp wrote: post #99
don-code wrote: post #87

Earlier quoted context omitted.

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…

What I don't understand is why it took you 8 weeks to distinguish a timer from a transistor. That doesn't make your professor's reaction alright, I just find it puzzling.

Ohm lordy, we're blaming the student for not having years of homebrew experience before he entered school? Sure any hobbiest knows what a 555 is, but when the lab assistant doesn't even catch it and the chip was handed out to the student this is not an entry-level students fault.

Re: Electron band structure in germanium, my ass (2001)

#327

Post by amy214 »

jerf wrote: post #27

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 stopw…

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.

Re: Electron band structure in germanium, my ass (2001)

#328

Post by analog31 »

janandonly wrote: post #2

It takes a special kind of mind to appreciate this short post, not as fiction, but as truth and also as a jab at the physics sciences in general.

I'm an industrial physicist, and the post put a smile on my face. And indeed, it's not fiction. It's a blast. You will go through times like this, I guarantee it.

I've been wrestling with a cantankerous experiment for a couple of weeks. It produces reproducible results, but they don't make sense, and the work is not in a domain where discovering new physics by accident is likely.

Re: Electron band structure in germanium, my ass (2001)

#329

Post by throwanem »

kragen wrote: post #314
sevensor wrote: post #228

Earlier quoted context omitted.

I would make them reread the MSDS.

I've seen an MSDS for sodium chloride USP that recommends against use in food, and says that you should wash your skin with abundant water for 15 minutes if you contact it and seek immediate medical attention if it gets in your eyes (after, of course, spending 15 minutes in the eyewash station). It also warns you to keep it away from sources of ignition, that it should not be released into the environment, and that y…

Fortunately, HF is as safe as NaCl. Or so I take you to suggest, this otherwise totally failing to follow from anything anyone has said...

Re: Electron band structure in germanium, my ass (2001)

#330

Post by hughdbrown »

opello wrote: post #323
anyfoo wrote: post #309

Earlier quoted context omitted.

No offense, but... when I was reading your story, I was somehow at least assuming that the marking on the part was somewhat unreadable or something... After getting befuddling answers, would it not have been natural to check the base assumptions, starting with do I have the correct part ? That is true as much in the "real engineering" world, as in school. You say "It could _never_ be the equipment's fault" as if it w…

Or even more likely in a lab setting: have another student test your part in their setup for A/B validation testing.

Sort of like the first debugging tip here:

https://news.ycombinator.com/item?id=42682602

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