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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)

#172
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…

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.

This is how I remember my own undergrad physics and chemistry labs: Terrible equipment and no time. The students who turned in faked but plausible data that looked like what the professor expected to see would get A's and the students who actually did the experiments and reported the crap they measured got lower grades. Everyone just learned the wrong lesson: Figure out what the data should look like and fake it.

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

#173
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…

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”

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

#174
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…

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…

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 complex problems to work out with pen and paper, tough stuff, lots of calculus. But the last question ended with “where does the electron live?”

That final problem, if you ignored the end wording, was super easy, something almost trivial to do with Helium iirc. The class had about 25 students in it; about 5 of us independently had the same thought: “this is a trick question, ‘the orbital is not a house in which the electron lives!’” And, independently, that’s how we five answered.

And we got marked wrong, all our course grades dropped to B+/- because of that one damn question.

Over a lunch or whatever, we discovered our shared experience and approached the professor as a group. He listened patiently and said: “Ah, right, I did insist on that idea, it’s understandable why you would think it’s a trick question and answer that way. But I still consider your answers wrong, grades stay as they are.” Some in the group even went to the dean and, to my understanding, he said it’s best to consider it a life lesson and move on.

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

#175
post #93

Earlier quoted context omitted.

If you like watching right-wing educational propaganda, sure.

It wasn't received as right-wing propaganda at the time. Endorsed by Bill Gates and others less-informed to education research with leanings towards the left. But it is definitely anti-education and proposes solutions that aren't justified, like the right-wing-aligned push for chartered schools (which tend to be religious in nature, hence the wholesale gobbling for it by the rightwing). Stanford studies in 2009 & 201…

> segregation (since poorer people both tend to be minorities and tend to not have capacity/time to jump through lottery hoops)

charter schools tend to have _more_ minority students than public schools. eg in philadelphia, charter schools are 80% black/hispanic versus 71% for the public schools. nationwide they are 60% black/hispanic vs 42% for public schools (https://www.pewresearch.org/short-reads/2024/06/06/us-public...). they're also generally lower income than public schools.

this is not super surprising because families with money already get school selection within public systems by virtue of spending more to live in better catchments.

i don't really have an opinion on charter schools being good or bad, but at least from what i've seen their primary audience is lower income families (often minorities) who look at their local public school and decide it's not good enough.

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

#176
post #151
post #124

Earlier quoted context omitted.

Same package. 555 is typically a DIP-8, transistor packages are available in the same. So you would have to examine the cryptic markings and compare them with the other students, and that’s only if you suspected some fuckup on the part of the knowledgeable people.

ALWAYS suspect some fuckup on the part of the knowledgeable people... especially them! Trust, but verify.

Yes, my strict adherence to “trust but verify” was born from literal tears. It’s not worth trusting others if it takes a small fraction of the projects time to verify. It has saved me incredible amounts of time in my professional life, and I’ve seen months wasted, and projects delayed, by others who hadn’t cried enough yet.

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

#177
post #67

Earlier quoted context omitted.

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 real…

We had the task of building a highly insulated small house. Big enough to hold a hot cup of tea (and meassure how good it holds its temperature inside). Our design was very, very good in that regard. (I used insulation building material from the house my family build at that time) But granted, it was not so pretty. But that was not a stated goal. But when it came to grades, suddenly design and subjective aesthetics m…

I mean, the other side of the coin is that engineering schools are a giant circle jerk that churn out thousands of graduates every year who if left to their own devices will design things that cannot be made out of inputs and using processes that are not appropriate.

I'm not saying you gotta prioritize looks but you gotta think a few steps ahead and understand what the ancillary criteria that will make or break a design all else being equal, or nearly equal are or what the unstated assumptions of the party evaluating your work (e.g won't look like ass, can be made in volume, etc.) are.

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

#178
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…

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.

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

#180
post #151
post #124

Earlier quoted context omitted.

Same package. 555 is typically a DIP-8, transistor packages are available in the same. So you would have to examine the cryptic markings and compare them with the other students, and that’s only if you suspected some fuckup on the part of the knowledgeable people.

ALWAYS suspect some fuckup on the part of the knowledgeable people... especially them! Trust, but verify.

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