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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)

#81
post #30
post #3

I spent a good minute looking at the exponential in graph, ignoring all the actual data points, thinking to myself that the experiment does show an exponential relation. Where's the lie? Guess that's the power pictures have over words.

There should be some more examples in how to lie with statistics?

I believe this is commonly known as marketing.

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

#82
post #7

A thing of beauty is a joy forever - John Keats Honestly, physics is so full of pretension and hero worship. Even among seasoned lecturers there's a tendency to mythologise the progress of the art by making it sound like all the great results we rely on were birthed fully-formed by the giants who kindly lend us their divine shoulders. Ironically there's a kind of Gell-Mann amnesia here, working scientists know that m…

On the contrary, what is presented by the OP is one of the many reasons that worship of science's heroes, unfashionable for decades, a whiggish pablum, is justified. If great results were birthed fully-formed -- a view I've frankly never heard anyone profess who has bothered to consider such things even briefly -- they would hardly be any heroes. Even little children who reflexively chomp on every superhero film aeroplaned towards their face understand this.

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

#83
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…

>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…

In the UK we called it ticket tape and it was terrible. The devices barely worked and they cause a bunch of friction so you end up calculating a value of 'g' that's off by like 30%.

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

#84
post #73

Earlier quoted context omitted.

And if you CAN'T terminate because of admitted emotional grading, the system is too tightly captured by outside interests to the detriment of the client: the student and society. A teacher is a professional entrusted with the most important responsibility society can offer: training and educating the next generation. It must adhere to the highest of professional standards and expectations. That we don't pay enough to…

Good watch - https://en.wikipedia.org/wiki/Waiting_for_%22Superman%22

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

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

#85
Oh, BTW, the whole "Friction is directly proportional to the normal force": My Ass!

I could never reproduce it well in the lab, because it's really not true. Take a heavy cube the shape of a book. Orient it so that the spine is on the floor. It's a lot more friction to move it in one direction than in the transverse direction. Yet the normal force is the same. Any kid knows this, and I feel dumb it never occurred to me till someone pointed it out to me.

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

#86

Earlier quoted context omitted.

> 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 i…

> he was angry, he marked it wrong. That’s grounds for termination to me. Seriously. I would put this man out of a job and endanger the livelihood of him and his family for this kind of shit.

There's a certain irony in your outrage at his failure to control his emotions, even as your own rage leads you to dream of hurting his family.

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

#87
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 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.

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

#88
post #85

Oh, BTW, the whole "Friction is directly proportional to the normal force": My Ass! I could never reproduce it well in the lab, because it's really not true. Take a heavy cube the shape of a book. Orient it so that the spine is on the floor. It's a lot more friction to move it in one direction than in the transverse direction. Yet the normal force is the same. Any kid knows this, and I feel dumb it never occurred to…

Is this possibly because you need to use additional force to horizontally stabilize it in one direction (perpendicular to the spine) but not the other?

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

#89
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…

Honestly, you got more real-world electronics training out of that experience than you paid for. You are now qualified to deal with remarked or counterfeit Chinese parts and other inevitable supply hazards in the business. Be grateful!
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