Sagan Jones, We know you can do better than him... - Page 1
Forum section: electronics / general

author: Zucca
author_rank: Unknown
timestamp: January 20, 2015, 10:32:40 am
content: And now the EEV folks are standing up, clapping their hands and screaming:SA-GANSA-GANSA-GANSA-GANSA-GAN....

author: zapta
author_rank: Super Contributor
timestamp: January 20, 2015, 03:47:04 pm
content: Very impressive, even with that extra zero. Will be interesting to see what kind of career this kid will have. Success is not guaranteed but is very likely.

author: Zucca
author_rank: Unknown
timestamp: January 20, 2015, 04:08:27 pm
content: Quote from: zapta on January 20, 2015, 03:47:04 pmAFIK Einstein was considered an idiot when he was an elementary school student. The opposite could happen for him, I hope not...The human brain, what a magnificent creation.

author: ampdoctor
author_rank: Frequent Contributor
timestamp: January 20, 2015, 06:04:49 pm
content: I know I'm going to come off sounding like a dick but I'm not horribly impressed and I see no genius here. If he had independently derived the algorithm it would be a different conversation. What you're looking at is the result of properly educating an eager child with an above average intelligence. Bravo to the parents! 50-60 years ago children were pretty much expected to know how to add, subtract, multiply, and divide by the time they were 7 or 8 years old. Kid probably never set foot in a state or federally run institution designed to reinforce mediocrity, conformity, and squelch anything resembling curiosity in young minds.

author: zapta
author_rank: Super Contributor
timestamp: January 20, 2015, 06:27:56 pm
content: Quote from: ampdoctor on January 20, 2015, 06:04:49 pmIt's not just the algebra, it's its application to the circuit, the handling of engineering units, the methodological solution, and the clear writing and presentation. Just awesome.As for Sagan, Dave mentioned once that he doesn't care what Noble prize he will get but for some reason he seemed to expect only one.

author: mtdoc
author_rank: Super Contributor
timestamp: January 20, 2015, 06:28:22 pm
content: Quote from: ampdoctor on January 20, 2015, 06:04:49 pmYep, but this kid is only 5.As the father of 6 and 8 year old boys, I can tell you the difference between 5 and 7 or 8 is huge.What's impressive to me is that this kids verbal and writing skills appear to be very good as well.

author: aargee
author_rank: Frequent Contributor
timestamp: January 21, 2015, 01:59:20 am
content: How do you know Sagan will be an engineer?Having an engineer father is no guarantee, no matter what they do at that age. I should know...

author: German_EE
author_rank: Super Contributor
timestamp: January 21, 2015, 10:55:49 pm
content: This is true, my father was a local government worker and in later life a preacher. Now, my grandfathers, one was a mining engineer and the other worked as a marine draughtsman in a shipyard.English question, is it draftsman or draughtsman where technical drawing is concerned?

author: EEVblog
author_rank: Unknown
timestamp: January 21, 2015, 11:03:16 pm
content: Quote from: zapta on January 20, 2015, 03:47:04 pmFrom the child "geniuses" I've seen, it seems like they all end up just in ordinary jobs, not becoming anyone of note.If true, my guess would be due to a lack of passion for anything. The parents just pushed them early.Being smart only gets you so far.

author: EEVblog
author_rank: Unknown
timestamp: January 21, 2015, 11:08:00 pm
content: Quote from: mtdoc on January 20, 2015, 06:28:22 pmAs only having an almost 4yo, no direct experience with older kids, but it's obvious to any parent there aredramaticdifferences between kids of the same age. And that even just 1 year can make the difference between chimp level skills, and the kind of stuff we see here. Every brain seems to grow and develop at vastly different rates.

author: mtdoc
author_rank: Super Contributor
timestamp: January 21, 2015, 11:33:39 pm
content: Quote from: EEVblog on January 21, 2015, 11:08:00 pmYes, very true. What I've seen in my own kids, their friends and the kids both myself and my wife see in our practices (I'm a family doc and she's a pediatrician) is that core abilities - motor skills, verbal skills, quantitative /analytic skills, and social skills - develop at different rates in different kids. This is especially apparent when they are very young since they are starting out as blank slates. You'er right, their brains are growing/developing rapidly but different brains show different patterns in how they develop. So while one kid may be very far ahead in 1 or 2 skills early on, they are often lacking or just ordinary in the others. Over time they all tend to even out so that by puberty the foundation of their innate talents has been laid. What happens from there of course depends on lots of factors.Interesting stuff and definitely something that keeps parents on their toes!

author: G0HZU
author_rank: Super Contributor
timestamp: January 21, 2015, 11:41:50 pm
content: Quote from: mtdoc on January 20, 2015, 06:28:22 pmYes, I was very impressed by his presentation and verbal skills too.BTW I solve it a slightly different way. I do it on a calculator as 8 (1/x) + 2 (1/x) = 0.625 then press (1/x) again and you get 1.6 ohms.where (1/x) is a press of the 1/x function key on an old school calculator.The reason I do it this way is because it's then also easy to then work out the solution to a similar puzzle:What resistor do you need to add across 8 ohm to get 1.6 ohm?answer = 1.6 (1/x) - 8(1/x) = 0.5. Press (1/x) again and you get 2 ohms.Hope I've typed that out OK as it's late and nearly bed time...

author: Rory
author_rank: Frequent Contributor
timestamp: January 22, 2015, 01:18:22 am
content: Quote from: German_EE on January 21, 2015, 10:55:49 pmIn the USA it's draftsman, or drafter.My wife is one, she uses Autocad. She spends her workdays working on valve maps for a gas pipeline company.

author: Zucca
author_rank: Unknown
timestamp: January 22, 2015, 09:11:04 am
content: Quote from: G0HZU on January 21, 2015, 11:41:50 pmWhy in EE 6 years university course nodoby told me that? So easy and so brilliant.G0HZUwere you a genius child?

author: EEVblog
author_rank: Unknown
timestamp: January 22, 2015, 09:21:16 am
content: Quote from: zucca on January 22, 2015, 09:11:04 amErr, that's the standard formula for parallel resistors!How you did not learn that in 6 years of EE is beyond me

author: Zucca
author_rank: Unknown
timestamp: January 22, 2015, 10:06:23 am
content: Quote from: EEVblog on January 22, 2015, 09:21:16 amA medic should know where the hands in the human body are.I meant the trick with the 1/x key on the calculator... I used to setup a formula on my TI-68 like this Zp=Z1*Z2/(Z1+Z2), it was working even with complex impedance too! What a beauty...BTW funny things are happening in Italy that can blow you away, and it is realistic to me you believed that could had happen for real to an italian EE...

author: darrylp
author_rank: Regular Contributor
timestamp: January 22, 2015, 10:45:05 am
content: Quote from: Rory on January 22, 2015, 01:18:22 amAnd the same in the UKSent from my HTC One using Tapatalk 2

author: rob77
author_rank: Super Contributor
timestamp: January 22, 2015, 11:43:43 am
content: actually i'm very sorry for that little boyhe's 5 and he is forced to do things he's not supposed to do... he's supposed to be a child at the age of 5 !and say whatever you want, he must have been forced to learn that !there are kids learning "crazy stuff" on their own (used to be one of them) but only learning the interesting part and they're presenting the learnt stuff the "child-ish way"... that's definitely not what we see on the video.but i might be wrong... and actually i hope i'm wrong.. otherwise his daddy would need some sessions at his psychotherapist...

author: Mechanical Menace
author_rank: Super Contributor
timestamp: January 22, 2015, 01:42:08 pm
content: Quote from: EEVblog on January 21, 2015, 11:03:16 pmFrom someone who was meant to be a "child genius" and had supportive but not pushy parents I don't think it's that. I'd say it's that the first time you come across something you actually have to try at and "fail*" to do is such a hit to your self esteem it puts you off of trying to push yourself. You go down a level to where you know you always get things right.Kids should be taught that failing and/or breaking things can be a learning experience. I'm 31 and only just got my head around that.*And failing can be as stupid as getting a B instead of an A*.

author: FrankBuss
author_rank: Unknown
timestamp: January 22, 2015, 02:01:23 pm
content: Quote from: zucca on January 20, 2015, 04:08:27 pmEinstein was good at school, seehttps://en.wikipedia.org/wiki/Albert_Einstein: "Contrary to popular suggestions that he had struggled with early speech difficulties, the Albert Einstein Archives indicate he excelled at the first school that he attended."

author: zapta
author_rank: Super Contributor
timestamp: January 22, 2015, 02:16:18 pm
content: Quote from: zucca on January 22, 2015, 09:11:04 amDidn't they teach you about mho units (1/ohm). You add them for parallel resistors.

author: zapta
author_rank: Super Contributor
timestamp: January 22, 2015, 02:23:18 pm
content: Quote from: rob77 on January 22, 2015, 11:43:43 amThat's a speculation.

author: Zucca
author_rank: Unknown
timestamp: January 22, 2015, 02:28:30 pm
content: Quote from: zapta on January 22, 2015, 02:16:18 pmSure, but everybody to get the parallel resitor was doing R1*R2/(R2+R1), I never saw somebody pressing/using the 1/x key.

author: zapta
author_rank: Super Contributor
timestamp: January 22, 2015, 03:09:20 pm
content: Quote from: zucca on January 22, 2015, 02:28:30 pmThat's a local optimization. Yes, nice trick, you enter each number only once. I use a quick spreadsheet.BTW, that kid beats me with long division.

author: Rory
author_rank: Frequent Contributor
timestamp: January 22, 2015, 04:17:02 pm
content: Quote from: zucca on January 22, 2015, 02:28:30 pmProduct over the sum method gets cumbersome if there are more than two values in parallel.

author: G0HZU
author_rank: Super Contributor
timestamp: January 22, 2015, 07:01:16 pm
content: Quote from: zucca on January 22, 2015, 02:28:30 pmYes, it's an efficient and intuitive way to do it because the 1/x key on an old school calculator acts as a rapid conversion to/from mho. You can also use it with series capacitors or parallel inductors.In the real world we have access to calculators and this method is therefore more efficient than the classic formula the kid was using. I've been using this 1/x key method for many years and once you have used it a few times it kind of sticks. I hoped a few people would not have seen it before so I thought it was worth posting on here

author: zapta
author_rank: Super Contributor
timestamp: January 22, 2015, 09:31:05 pm
content: Apparently mho units are also called Siemens. Never heard of it before.http://en.wikipedia.org/wiki/Siemens_%28unit%29

author: Howardlong
author_rank: Super Contributor
timestamp: January 22, 2015, 09:37:19 pm
content: Quote from: zapta on January 22, 2015, 09:31:05 pmShowing your age

author: rob77
author_rank: Super Contributor
timestamp: January 23, 2015, 07:19:37 am
content: Quote from: Howardlong on January 22, 2015, 09:37:19 pmit's not about age, it's about location...i never heard about "mho" before (ohm in reverse ?) , but Siemens is a widely used unit over here in Europe.

author: zapta
author_rank: Super Contributor
timestamp: January 23, 2015, 07:38:00 am
content: Quote from: Howardlong on January 22, 2015, 09:37:19 pmYes, too old, Siemens wad not born yet when I was in college.;-)

author: EEVblog
author_rank: Unknown
timestamp: January 23, 2015, 07:41:41 am
content: Quote from: zucca on January 22, 2015, 10:06:23 amIt's not a trick, it's that's the most used and standard formula!1/Rp = 1/R1 + 1/R2IME the majority of sources that teach parallel resistors use the reciprocal method instead of the product over sum method. Both very often both.That's why I'm surprised you've never seen it.Probably more popular than product over sum because it is easier to do on a calculator.On an algebraic, for a single digit resistance, 7 keystrokes vs 10 keystrokes.

author: mtdoc
author_rank: Super Contributor
timestamp: January 23, 2015, 07:50:10 am
content: Quote from: zapta on January 23, 2015, 07:38:00 amIn college before 1881? Wow - you are old!

author: IanB
author_rank: Super Contributor
timestamp: January 23, 2015, 08:11:37 am
content: Quote from: zucca on January 22, 2015, 02:28:30 pmThen how would you determine the parallel sum of three or four resistors, like R1||R2||R3||R4?The standard formula for that is:1/R = 1/R1+ 1/R2+ 1/R3+ 1/R4+ ...It's going to get very messy if you do it any other way. It is completely astounding to me that you have not learned this standard formula in high school, let alone college. (In fact, I think perhaps you are not serious and you are pulling everyone's leg?)By the way, the origin of this formula is why there was a much easier way to solve the problem on the blackboard than the way used by that child:I1= 8 V / 8 ohm = 1 AI2= 8 V / 2 ohm = 4 AIT= 1 A + 4 A = 5 ART= 8 V / 5 A = 1.6 ohmAn older and more experienced person would have seen this method and intuitively applied it rather than solving the problem in the order given by the question as the child did.

author: IanB
author_rank: Super Contributor
timestamp: January 23, 2015, 08:20:17 am
content: Quote from: German_EE on January 21, 2015, 10:55:49 pmIn America it would be draftsman, in Britain it would traditionally be draughtsman, but the American spelling is seen more often in Britain these days due to global American influence.

author: lapm
author_rank: Frequent Contributor
timestamp: January 23, 2015, 08:22:40 am
content: Few more years and Sagan can take over fundamental fridays

author: coppice
author_rank: Super Contributor
timestamp: January 23, 2015, 08:26:47 am
content: Quote from: EEVblog on January 21, 2015, 11:08:00 pmThe youngest and oldest kids in a class are generally one year apart in age. In the early years of school it really shows, both physically and mentally. The mental differences aren't that well documented, but some physical ones are. Hardly any US baseball stars were born in the second half of the year. They get picked for development while young, based on the year they were born and their performance. The kids who are a few months younger stand no chance at all in these selection tests. They never get into the development program, and they never become stars. My experience with the mental abilities of children are similar. Any early selection of children as exceptionally smart in their class will massively favour the oldest in the class.

author: Zucca
author_rank: Unknown
timestamp: January 23, 2015, 08:55:14 am
content: Quote from: EEVblog on January 23, 2015, 07:41:41 amI´m not taking about the formula or theory, the point is the 1/x key on the calculator!In your experience and known world is the most used (and surely your E/E experience is much bigger than mine), but there are EE people you don´t know out there (less than 1% at this point, maybe?) like me who for decades never touched the 1/x key on the calculator for parallel resistance calculation. I promise you I´m not alone. BTW I´m pissed with my well paid professors who didn´t told me:"Dears students just use the 1/x key to save time". Sometime the easiest way can be very clear and simple, but if you don´t know it and you know a way to do get what you need, good luck to understand you are losing time!Quote from: IanB on January 23, 2015, 08:11:37 amRp12=R1*R2/(R1+R2)Rp123=Rp12*R3/(Rp12+R3)Rp1234=Rp123*R4/(Rp123+R4)Very long and stupid way once you know how to use the 1/x key. Is the result a wrong one? No, so that´s why I was keep going like this, of course for massive calculation Excel was my best friend.Now, wait a minute. Probably once I tipped on mine TI-68Code:(Z1 [1/x] +Z2 [1/x] +Z3 [1/x] +Z4 [1/x] ) [1/x]where Zn were complex impedance, please note that [1/x] means the 1/x key.It could be I used evenCode:^-1wihch means 3 keys on the calculator, not sure about that. Probably no, I am more crazy than stupid.Quote from: IanB on January 23, 2015, 08:11:37 amOf course I saw that equation and also used it! The whole point is it never clicked in my mind to use the damn1/x key, and I thankG0HZUfor telling me that.It also depend on the calculator you had. If you had one which after pressing [1/x] was displaying immediately the result then probably this discussion makes you LOL.Mine by pressing the [1/x] was just putting the -1 at the exponent and sitting there, to get the result you had to press .Anyway good for you and bad for me. Case closed. I already lost enough time by no using the 1/x key. Please forgive me but in this discussion I have the feeling I am wasting my time by talking about how I wasted my time in the past. I am not irritated at all, I am just facing the crude reality LOL.PS: I miss now my old trusty TI-68 soo much, we won a lot of battles togheter! It was declared dead two years ago, the display was just showing garbage all the time. May his soul rest in peace.http://www.datamath.org/Sci/Modern/TI-68.htm.

author: IanB
author_rank: Super Contributor
timestamp: January 23, 2015, 07:46:53 pm
content: Quote from: zucca on January 23, 2015, 08:55:14 amI guess this is a downside of things like S.V.P.A.M. (Super Visually Perfect Algebraic Method) and its various equivalents on calculators in recent years. I dislike these things because they stop you juggling with numbers and seeing the results as you go along.