You blokes amaze me. I had mine for years.Quote:
Originally Posted by Mr Brush
It only left me in tears and very sad. Damned thing boggled my mind :(
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You blokes amaze me. I had mine for years.Quote:
Originally Posted by Mr Brush
It only left me in tears and very sad. Damned thing boggled my mind :(
I found once I had worked out what a "stack" was and how it operated it was quite easy.Quote:
Originally Posted by woodPixel
Yup, to we RPNites, "brackets" is a dirty word :D. Stack trumps brackets every time.
Must admit it was fun when someone borrowed my HP calculator......just to watch them scratching their head for a while before they asked "Where's the equals key?"
The hp45 was the go when i was a student.
Being a poor student, i made do with a clone, the corvus 500.
I stumbled across it the other day. I ought to see if it will fire up... (or perhaps smoke up..
Hows $1.50 for a Kg of Hydrogen!
New doodad is 95% efficient.
This will do quite nicely for storage of Wind/Solar and remotes.... NICE!
Record-breaking hydrogen electrolyzer claims 95% efficiency
I imagine hydrogen will form part of the future energy mix as a storage system and it's great that they've managed to reduce the price. However, there are number of issues I now see with hydrogen. Firstly, at ambient pressure it only has 11 MJ/m3 whereas petrol stores about 36,800 MJ/m3. So it requires compression which requires energy and creates heat which is probably lost in process. Storage costs and transportation are also very high. Batteries are about 90% efficient whereas hydrogen is about 41% using fuel cells and 35% using combustion. That's a huge waste of green power when it could be used elsewhere. I cite Saul Griffith's book The Big Switch as my data source.Quote:
Originally Posted by woodPixel
Griffith's overall message is electrify everything which uses energy. He posits that wind and solar convert natural energy directly into electrical energy whereas every other system converts its inherent potential through other forms of energy before generating electricity, and each time it converts, efficiency suffers. The beauty about wind and solar is that it is easily and inexpensively established versus the minefield of approvals needed for either fossil or nuclear fueled facilities; to say nothing of their capital cost and lead time.
mick
This is most interesting.Quote:
Originally Posted by Glider
I saw a video where the maker said exactly this.
The Interviewed was asked why the USA was putting in such an astronomical quantity of solar. He cited the fact the approval was a local bumpkin council (easy - literally anyone can install it en mass, starting Next Tuesday) whereas a nuke plant was a regulatory hell (cost, specialists, regulation, 10 year builds, specific places, etc, etc, etc)
Just bought :) Thanks for pointing it out.Quote:
Originally Posted by Glider
The Big Switch by Saul Griffith | Black Inc.
This is a small adjunct to the electrification-of-everything.
Robot Truckers Could Replace 500K U.S. Jobs
and
Can a Self-Driving 40-Ton Truck Be Safe? Developers Say Yes - Bloomberg
Imagine having the truck simply as a big battery and motors, with a supplemental battery in the bogie. These things can putter back and forth, perfectly safe, on long haul deliveries.
Obviously not for the Nasty Parts (crappy roads, inner city to outer depot), but obviously very suitable to big chunks of Australia.
It might prompt a man to go into the truck hijacking game.Quote:
Originally Posted by woodPixel
mick :)
AlexQuote:
Originally Posted by AlexS
Bit like this perhaps except we called them "Four Figure Tables" and you can see why from the cover. :rolleyes: Mine date from 1965.
Attachment 509090Attachment 509091Attachment 509092
I have been away from home for a couple of weeks so had no access to ancient hoarded treasures. I only ever used these in exams. Calculators were not allowed.
Regards
Paul
This will be very nerdy, but when I can't sleep I do square roots in my head to four digits. :)
I'm unwell :)
Square root of 2 = 1.4142135, 3= 1.7320508
WP, I think we share some common traits.
ajw
Its not hard to work out on paper, but the trick is keeping the totals in working memory. It can be quite challenging.
I often fall asleep 😂😸, or if I can't clear my mind this works wonders. Its akin to a meditation.
They're the same ones I had at school. Must have been the standard issue. Later, at tech, I bought a set that had all the physics info inside the covers.Quote:
Originally Posted by Bushmiller