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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)

#301

Post by timewizard »

oddmiral wrote: post #210
shadowgovt wrote: post #122

Earlier quoted context omitted.

What would be the process to do that? To aim 0 and 100 properly, you'd need a tool to calculate a 100:28 (25:7) ratio on an arbitrary distance, wouldn't you? One can build such a tool, but it's not a doubled-over piece of string.

Make marks on the thermometer at 0 and 100 degrees C, then project light from a candle to a wall to see these marks with say 5x magnification. Now project marks from the 128 mark ruler to the same wall and align marks from both, then place marks on the thermometer with 5x better accuracy.

A candle is an exceptionally unstable light source. The flame continually moves location as it burns. Any air currents in the room will disturb it and cause flame shadows to be cast. Adding magnification will just make this all worse.

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

#302

Post by timewizard »

shadowgovt wrote: post #62

This reminds me of how the Fahrenheit scale came about. For all its flaws, Fahrenheit was based on some good ideas and firmly grounded in what you could easily measure in the 1720s. A brine solution and body heat are two things you can measure without risking burning or freezing the observer. Even the gradations were intentional: in the original scale, the reference temperatures mapped to 32 and 96, and since those a…

They say two points but it was really three. The ammoniac mixture at 0F, water freezing at 32F and body temperature at 96F.

Also Celsius, for whatever reason, originally put boiling at 0 and freezing at 100. Maybe Sweden is just that cold.

Jame's Burke's "Connections" series covered this in series 3 episode 10. Here's that clip:

https://youtu.be/w4ujTt0gDx8?si=XUV9J3srYdaBwqwm&t=1227

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

#303

Post by potato3732842 »

lukan wrote: post #262
potato3732842 wrote: post #177

Earlier quoted context omitted.

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 des…

The main design goals were: - construct a house with good insulation No word of it being pretty. Houses should look pretty, but it wasn't art class, but physics. And the physics teacher clearly said insulation is the goal (so we learn about the concept). We had a funtional house (roof, walls, windows, door) with very good insulation. The winning house just looked pretty and its insulation was basically nonexistent.

I get that, and think that "pretty" is a dumb goal because what's "pretty" is usually just cargo culting of whatever works. But I think reading your customer is a useful lesson, but probably should be taught intentionally not accidentally via bad teaching.

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

#304

Post by m463 »

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…

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.

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

#305

Post by promiseofbeans »

The main lesson I was taught by undergrad chemistry and statistics is that the point of science is to lie and massage your terrible incorrect results until they look realistic, claim any remaining error was due to the shitty inprecice equipment you're saddeled with, and turn it in, because you don't have enough time or money to try again.

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

#306

Post by RunSet »

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

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

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

#307

Post by pshirshov »

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…

Did the same. Least squares got me to 9.7

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

#308

Post by lucisferre »

roadbuster wrote: post #39

I read this in 1999 when entering university. It was so refreshing hearing a student provide a glimpse into the boots-on-the-ground reality of undergrad life at these world-renowned institution. The closing sentence is also prescient; the author pivoted to CS, ultimately completing his doctorate at the University of Wisconsin at Madison https://pages.cs.wisc.edu/~kovar/

I read it about the same time. My friends and I (all of whom declared Physics and most of us switched to other majors before graduating) had tears in our eyes reading it. Funniest thing I had ever read.

I'm glad he's doing well.

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

#309

Post by anyfoo »

don-code wrote: post #118
orlp wrote: post #99

Earlier quoted context omitted.

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.

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 was, but it wasn't. The test equipment gave you correct answers, your device under test was wrong.

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

#310

Post by anyfoo »

mikepurvis wrote: post #113
orlp wrote: post #99

Earlier quoted context omitted.

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.

That would be like exposing a first year CS student to a situation where "it could be a compiler bug" is one of the potential explanations.

The part was marked as a timer IC.
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