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Cake day: June 16th, 2023

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  • Solid fuel for rockets burns relatively slowly at 1 atm and in solid form, much like a flare, though still faster than I would expect you’d want for a hot pot unless these were a hybrid (so no oxidizer in the pellets, just a solid fuel source like modified PVC, with a separate oxidizer like nitrous oxide). The water was replacing the jet fuel, which - assuming it was similar to Jet A - is basically kerosene. Though I’d be worried what modifiers or stabilizers were used for a green flame if I were cooking over it. I’ve made green flames with boric acid and methanol for Halloween decorations (outdoor, of course), but who knows what is causing it in their fuel.


  • Having lived through it, it really does feel weird though. I (mostly) missed the gasoline crisis (I was a child). It’s hard to imagine gas pumps all over the US being out of gasoline, and mile long lines waiting for a tanker to show up so you could get gas. It’s pretty much impossible to imagine staple rationing (butter, sugar) during wartime in modern US. I certainly didn’t live through it - having the TP aisle empty during covid doesn’t quite match that. And the actual (1930s) depression. I suspect those folks would consider the crashes of 87 99 01 08 and 20 minor annoyances - a bad Tuesday - compared to what they lived through.

    Think of this, though - you have Covid. Okay we have Covid. That’s a world-wide event with life-changing implications for so many. And, we can hope, we don’t get another pandemic event of that magnitude in our lifetimes. And a decade or two from now you can lord it over some kid who was born in the last 3 years and just “doesn’t understand” that “closing school for three days because the flu is so bad” is not a pandemic, and that they just don’t understand what a game changer Covid was. ;-)



  • Interesting that I learned 32.2 ft/s, but only 9.8 m/s - one less significant figure, but only a factor of two in precision (32.2 vs 32 = .6%; 9.81 vs 9.8 is only 0.1%). Here’s the fun part - as a practicing engineer for three decades, both in aerospace and in industry, it’s exceedingly rare that precision of 0.1% will lead to a better result. Now, people doing physics and high-accuracy detection based on physical parameters really do use that kind of precision and it matters. But for almost every physical object and mechanism in ordinary life, refining to better than 1% is almost always wasted effort.

    Being off by 10/9.81x is usually less than the amount that non-modeled conditions will affect the design of a component. Thermal changes, bolt tensions, humidity, temperature, material imperfections, and input variance all conspire to invalidate my careful calculations. Finding the answer to 4 decimal places is nice, but being about to get an answer within 5% or so in your head, quickly, and on site where a solution is needed quickly makes you look like a genius.


  • Yeah, that’s just a shitty (or out of spec) time base. My Seiko watch gains 1-2 minutes a day, but it’s completely mechanical so it depends on temperature and winding/mechanism tension for accuracy. There are electronic timing circuits which are resistance and capacity based, and as the resistance and capacitance of the system drift (time/age and temperature) they also drift. A crystal, made to vibrate at high frequency (piezoelectrically, iirc), will provide a much more stable time base and be accurate to seconds over many days’ time.

    Interesting aside - time keeping is how ships at sea used to determine where they were in the ocean. Latitude can be found from the stars, but longitude can’t so it needs a time reference standard. The book, Longitude tells the story of the search and the competing methods for determining location prior to the invention of crystal/electronic time bases and modern GPS. I won’t say that the storytelling is particularly gripping, but the actual path to discovery is fascinating.


  • That’s probably just fluctuations in the line frequency and the method for keeping time varying between the two (one might use a crystal that drifts). Being on the “wrong” frequency will have it shift by hours every day. I had a (US/60Hz origin) microwave in my apartment in Bonaire (50Hz) last year that never seemed to have the right time, and when I did the math I realized it was the frequency - it was behind by ~4 extra hours every day (50/60 x 24 hours).



  • Overzeetop@kbin.socialtoAsk Lemmy@lemmy.world*Permanently Deleted*
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    11 months ago

    I’m not rich enough to hate Google. I have a couple of domains and several people who use them for email. I have calendars with people across device ecosystems. I don’t have the hours and hours to keep up with fighting spammers or an infinite budget to hire someone else who will guarantee my privacy to do it. What are my options? Is Microsoft or Yahoo any better?

    I’ve been with Google since they were a Do No Evil company. Now that they Do Evil, they already have terabytes of my old data in storage to mine. Adding a few more GB isn’t going to make a hill of beans difference.

    Also, I recognize nuance - Google, well Alphabet, isn’t one company. It’s a huge conglomerate of, sometimes competing, interests. That’s a distinction that often gets lost in online discussions. Whether I hate Youtube’s profit arc or not doesn’t really affect my impression of the Gsuite services I rely on.






  • Clear containers for anything that isn’t commercially labeled. My wife used to wrap leftovers (or anything, really) in aluminum foil. more than two thirds of the time I’d end up throwing it out after a couple of weeks because, since nobody knew what was in the mystery packages, nobody ate it. I bought some glass storage containers (the kind with the plastic, locking lids) so it’s obvious what is contained within. A lot less waste.

    Also, I’ve got pull-out bottom freezer with one basket and one deep “bin” and shit got lost so I 3D printed dividers and organized it.


  • That would require making more land and increasing the capacity of existing high-use, aging infrastructure for water, sewage, power, and trash. I can find you a cheap place to live out in the sticks. Hell, the town down the road from me has brand new, 3BR 2.5BA 1900SF homes with garage for $270k (USD). You only need 2BR/1BA and 1100SF? $150k. Thing is, it’s a 30-40 minute drive to the center of my 200,000 person MSA. But this isn’t a fun, entertaining city with excellent walkability, public transit, a major airport, and multiple concert venues and public spaces so people aren’t flocking to move out here.