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6:59 AM
Hi everyone. The following question contains two answers:
2
Q: Why do we get electric shocks when most structures are insulators?

KarnivaurusSuppose I was standing in the sea, and touched an electric fence; I would receive an electric shock, because both my body and the sea are conductors, and create a path for the electricity to flow. The sea is so big that it has the capacity to draw and dissipate a great quantity of charge. However...

But neither of the two have enough details. What is the best way to get more informative answers?
Will starting a bounty be helpful? I'm asking this because two of my bounties I started on a different site went in vain. I didn't get even a single answer. Are there any alternatives? Kindly guide me in this regard. Thank you.
 
7:40 AM
Please explain this statement,"The solute atoms are able to diffuse in the specimen at a rate faster the speed of dislocations so as to catch and lock them.Therefore the load must increase and when the dislocations are torn away the solute atoms there is a load drop."
 
7:54 AM
@JohnRennie Good morning
 
@M.GuruVishnu is that OK?
 
I looked a little more yesterday regarding how the phycists think about physics. My impression is that in different models things may either have indefinite states (position, momentum etc) (case 1, Copenhagen interpretation etc) or have definite states (case 2: pilot wave theory), but it doesn't seem to matter much as it might not be too clear how exactly unknowability (hidden variables in case 2) differs from uncertainty (case 1).
I know little about decoherence, (did not get into the linear algebra), but according to some description, it seems that decoherence is somewhat viewed by some as leaking? information from a system to another. And from the point of view of an observer in another system, there could be a definite outcome (a.k.a. a measurement happens).
There is also a thing called the rate of decoherence so that even though every thing is interacting with every thing in the observable universe, a wave function might not be 'collapsed' much if it's a weak interaction (ex. very weak gravitational pull, or encountering a photon with little energy etc.)
There is also a perspective problem (ex. Wigner's friend): if a measurement happens between system 1 and system 2, to an outsider system 3, does the the wavefunction of system 1+2 change if no measurement happens between system 1+2 and system 3 yet. I guess system 1+2 would still appear in a superposition for system 3 if system 3 does no measurement on it but I guess it doesn't make much difference from an observer point of view.
 
8:16 AM
@yuvrajsingh Your reply gave me a hint that you added your answer there. Thank you.
 
@frt132 morning :-)
 
 
1 hour later…
9:39 AM
Welp
Sent a new mail to Princeton
I hope they can send me that bloody thesis
 
hey howarya
 
10:07 AM
@JohnRennie If possible, could you take a peek at what I wrote and let me know if that makes any sense to you? You don't need to explain anything, thanks a lot!
 
 
2 hours later…
12:32 PM
I'm considering putting a bounty on this question?
-2
Q: Why can this potential be snuck in producing non-unique Lagrangians?

More AnonymousBackground So if I think of a gas of say having only $2$ point particles $A$ and $B$. Then, the Hamiltonian in the relativistic case is given by: $$ H_1 = \gamma_A m_Ac^2 + \gamma_B m_Bc^2 $$ where $\gamma= \frac{1}{\sqrt{1 - v^2/c^2}}$ and $m$ is mass. However, this doesn't really make sense...

Is that okay? It was possibly in stage of being voted to close but I think I have edited it and salvaged the situation
I'm not sure of the procedure since I don't want to interrupt the proceudre
*procedure
 
@MoreAnonymous The close review is not yet finished (but there's no way you could tell)
 
@ACuriousMind Which is why I'm confused :/ (in response to "but there's no way you could tell")
Can I risk it?
 
Yeah, the feedback to users w.r.t. reviews isn't great.
@MoreAnonymous Given that both close votes that currently are on the post were cast after most of your edits (something you also can't tell, I know), we would likely remove the bounty to let the close review be finished first. So no, please don't put a bounty on that.
 
@ACuriousMind Can I wait for a day or 2 and then consider?
Putting a bounty?
 
You shouldn't be able to put a bounty on it right now anyway since the question is less than 2 days old.
 
12:47 PM
Ah, just saw that :P my bad
But is there a good time limit you'd recommend?
 
Frankly, I would not recommend bountying that question in its current form at all, since it is entirely unclear. For starters: You talk about equations of motion but never actually write down a single such equation. You add that $\delta$-term to your Hamiltonian and seem to believe it somehow changes the behaviour during collisions but you haven't done anything to show that.
 
@ACuriousMind Thanks for letting me know what to edit :)
 
user439435
1:04 PM
1
Q: Why does pressure varies with depth in a fluid at microscopic level?

user 249451Before asking this question I searched for the answer on the web (in particular on Physics.SE) and here are some that I found: In an incompressible Ideal fluid, can the pressure increase with depth? Why do water molecule apply more pressure (i.e., more force) at depth? ..., etc. But the answe...

 
1:37 PM
@M.GuruVishnu I think your best bet is a bounty still. If it doesn't work out, then I guess that's just what is going to happen. Although keep in mind that the amount of points you put up might affect the attention it gets
 
@AaronStevens Thank you for your suggestion :-)
 
@AaronStevens Good morning. I apologise if I was rude to
you on that day because of him
 
^No point in teaching students stuff which ain't true, rather contradictory to each other and possibly incomplete
 
@AbhasKumarSinha Hi
 
@Knight hi
 
1:52 PM
Can you help me Lorentz force law?
 
@Knight Notta very good with electrostatics, show me the question
 
Actually, the thing is Magnetic forces do no work and the proof goes like this
 
@Knight Magnetic Forces also do work
@Knight problem is just that force is perpendicular to motion or $$ F.v = 0 $$
No proof required... Force must be in the direction of motion in order to do work...
 
>If the charge is moving with some velocity $v$ then the force on it is $ q(\mathbf{v}\times\mathbf{B})$ and the distance $d\mathbf{l}$ that it travels can be written as $$ d\mathbf{l} = \mathbf{v}dt$$ and therefore the expression for work will be $$ \int \mathbf{F} \cdot d\mathbf{l} = \int q(\mathbf{v} \times \mathbf{B}) \cdot \mathbf{v}dt = 0$$
 
@Knight correct
@Knight For any vector $$ (\vec a \times \vec b ).\vec a = 0 $$
Where a and b are perpendicular
 
1:59 PM
But the problem is why he has replaced $d\mathbf{l}$ by $\mathbf{v}dt$. The definition of work says "Force times the displacement caused by that force" but here he has not used the displacement caused by the force rather he has taken the original displacement
 
@AbhasKumarSinha There's a lot of point in teaching students Newtonian mechanics though. It's approximately true and can give very useful models for the macroscopic non-high speed world. You can have entire careers and fields based on newtonian physics.
 
@AaronStevens Can you help me with this?
 
@Knight $$ dl = v \, dt \\ \dfrac d {dt} l = v$$ is a kinematic assumption and can't be proved...
@JMac That's what I said, QM and GR seem rather very absurd and incomplete and have a scope of a lot of improvements in the future. Rather Newtonian Mechanics can be shown working
 
No the problem is $dl = vdt$ is the equation that we use if the particle were traveling with $v$, we should take $dl$ that is caused by the force and which must be in the direction of the force
 
@AbhasKumarSinha QM and GR are technically more true than newtonian mechanics though. They can more accurately describe phenomenon where newtonian mechanics fails, and still seem to come out to the newtonian solutions when the conditions of newtonian mechanics are met.
 
2:06 PM
@JMac That's true, but modern physics have a lot of scope for improvements, teaching QM now doesn't gurantees that the QM would be same as today after 60 years. Personally, I align myself to the group saying God does not play dice Even though there might not be any hidden variable, but another equation apart from Sch eqns, to describe the system correctly...
 
#bless
Taking a selfie at the mall everyone #lifeisawesome #fashion #friends
 
@AbhasKumarSinha Newtonian mechanics doesn't describe everything perfectly either though, that's why we have QM and GR at all.
 
@JMac Who told that Newtonian Mech, describes everything perfectly...
@NovaliumCompany ...?
 
@AbhasKumarSinha Well it was an attempt to describe how things worked in general. Newton never specified that it was only for low velocities and that it had limits due to the speed of light. He never mentioned that it broke down at microscopic scales. It is an incomplete model, moreso than QM for example, because QM can explain newtonian mechanics and high speed situations.
 
@JMac Statistical Mech is generalisation of both QM and GR and String Theory, is the generalisation of all.
 
2:13 PM
@ACuriousMind, actually the question was same with, the title, please reverse back your decision.
 
@AbhasKumarSinha Okay, and they all presumably describe reality better than newtonian mechanics.
@yuvrajsingh physics.meta.stackexchange.com/questions/12580/… Here is the meta discussion where the decision is explained.
 
There is word complete different, which not work on my question, I haven, t edited the title in fact, and make the question suitable with article. @ACuriousMind @JMac
 
@yuvrajsingh You asked a question and it was answered - if you have a different question, you should ask it as a new question. It is not fair to the people who answered if you completely change the content of the question.
 
Brother earlier the question not justify my title, in fact posted the question, when I was very very fresh user on the site, today I updated the question. With suitable subject.
 
Can I ask economics questions here?
 
2:20 PM
I understand that it is not fair for others who answered the question, but seriously it is not totally reverse the question.
 
@yuvrajsingh You're right that the title doesn't fit the actual question. So you should edit the title, not change the question!
 
@Rohan You can ask about some concepts
 
-1
Q: Expected payoff in N bidders in a FPSBA

RohanAccording to Bayesian Nash equilibrium In a two player first-price sealed bid auction I know that expected payoff is given by 2*v1*s1 - 2*s1*s1 where s1 is the bid price of player 1 and v1 is the valuation. In a first-price sealed bid auction with n risk-neutral agents whose valuations are indep...

 
Actually brother title describe what actually I want to ask, but when I join the site, how to define subjective part.
 
@Rohan You should ask this on problem solving strategy room
@AaronStevens Are you here?
 
2:21 PM
I am looking for formula that would help me calculate expected payoff in a bayesian nash equilibirum for a three player game
 
@Rohan I think as far as I know, there is no one in problem solving strategies, who know economics.
 
@Knight You are supposed to do the integral along the path the particle moves along. So replacing dl with v dt is correct
Also one notification is sufficient. You don't need to ping users multiple times
 
@yuvrajsingh bro this might be simple if anyone knows calculus
 
@yuvrajsingh You're title may have described what you wanted to ask, but the body of your question asked something quite different, and people gave you answers about that. I don't see how it's fair to make their answers invalid because your title and question didn't really match.
 
I edit the correct, and motive of edit to make the question, more correct, regarding the title. @JMac
 
2:25 PM
@yuvrajsingh Please stop calling me "brother". What you wanted to ask doesn't matter, what matters is the question you asked and you don't get to completely change that now. In particular since this appears to be your attempt to ask a new question even though you are currently blocked from asking further questions.
 
@AaronStevens I'm saying that displacement will be in the direction of the force, becasue the force will be perpendicular to velocity and particle will move perpendicular to its initial velocity.
 
@yuvrajsingh Actually... looking at the question history, it should be rolled back and closed as a duplicate again. The question was closed as a duplicate on June 9th, the same day you got those answers. The question didn't ask about heat. physics.stackexchange.com/revisions/485084/6 Changing the question completely like that is not okay to avoid a duplicate...
 
@JMac What all happened, I just left my computer for a few minutes....
 
@ACuriousMind I think it is a common trend for Indians to address each other as brother, he didn't mean that sarcastic brother
 
@AbhasKumarSinha Just some disagreement about how to handle a question.
 
2:29 PM
@JMac uh okay...
 
@Knight I didn't take it as sarcastic or anything, I simply don't like being addressed that way
 
@ACuriousMind Yeah, it doesn't feel well sometimes
@AaronStevens Are you busy?
 
Rather calling Bro, sounds good...
 
@AbhasKumarSinha No, just see @ACuriousMind 's profile. He should be respected and should not be called brother.
 
@yuvrajsingh physics.stackexchange.com/posts/485084/revisions ... really, you did it again? It should be rolled back to revision 6 when it was asking something completely different and closed as a duplicate. You can't completely change a question because it's closed as a duplicate, you need to ask a new question.
@Knight The profile shouldn't matter. If someone doesn't want you to call them brother, you shouldn't.
 
2:33 PM
@Knight That's why i address him sir.
 
@JMac Yes. They should realize that age difference
 
@ACuriousMind sorry for calling brother I haven, t seen ur profile.
 
@Knight Yes, rather should be called Uncle?
 
...I'm deeply confused what my profile has to do with anything
 
@yuvrajsingh It looks like you're changing your old question to get around your question ban. That is definitely not ok. As ACM said:
 
2:34 PM
@Knight Age difference doesn't matter either though. If someone doesn't want to be called brother... just don't call them that.
 
@Dale Yes. If OP has a new question, they can simply ask a new question. (If they can't because they are blocked by the system from asking further questions, then they are trying to circumvent that restriction, which we also shouldn't accommodate) — ACuriousMind ♦ 1 hour ago
 
@ACuriousMind Nothing sir
@JMac Why he was banned though?
Cyber Warfare^
 
@AbhasKumarSinha No idea. I have nothing to do with banning people.
 
Recently, the parliamentarians passed a new law in US, which assumes space as a place for war...
 
@ACuriousMind Your profile shows that you are not a student and hence must be having more knowledge and experience than an undergraduate, that's what I meant.
 
2:37 PM
@PM2Ring @j Mac @ACuriousMind, I really sorry if some how, I disrespect the site and you, but this was the question which I want to ask, when I join the sitem
 
@JMac Well I was banned loooooooooooong ago, I didn't knew how to ask questions on SE though, got -6 downvotes in a single day :P
 
@Knight You shouldn't call an undergraduate "brother" either if they don't like it!
 
@JMac Can you help me with that magnetic forces do no work.
@ACuriousMind Yes. I agree.
 
@yuvrajsingh You should rather ask question here, rather than spamming...
@yuvrajsingh Have you checked, there are not any similar questions around!
@yuvrajsingh If someone is not Indian, don't call him bro, they take it as a offence...
 
Yes I asked it from the John sir, and I got an excellent answer, no this kind of question haven, t asked.
 
2:38 PM
@yuvrajsingh then ask...
 
@AbhasKumarSinha OK, but at my college we have seniors, I call them bhai.
 
@yuvrajsingh Ok. But it's far too late to change your question now. It's ok to make small edits to make the question more clear, or to improve the grammar. But you should never make edits that cause existing valid answers to become invalid.
 
@AbhasKumarSinha Matter is not being Indian. Brother is not something very acceptable in other societies.
Why no one is helping me with my "magnetic forces do no work problem?"
 
@yuvrajsingh Don't call them, learn to address people when you are in a different culture.
@Knight What's the problem?
 
2:41 PM
@AbhasKumarSinha Why $dl =vdt$ , $dl$ should be taken in the direction of the force
@ACuriousMind Can you help with my question?
 
@Knight no, $t$ isn't a vector first, and any equation in the form of $$ \vec a = c \vec d $$, then $ \vec a $ and $\vec d$ are in same direction..
@Knight So, $v$ and $dl$ are in same direction.
 
@AbhasKumarSinha Please re-read my problem.
 
@Knight no, $v$ is prependicular to force and $dl$ is in the direction of force...
Re-read some good book on vector..
@Knight You got the answer now?
 
@AbhasKumarSinha So, $F\cdot dl$ should not be zero because you have said dl and force are in same direction
 
@Knight When I said?
 
2:46 PM
@AbhasKumarSinha here
no, v is prependicular to force and dl is in the direction of force... $dl$
 
@Knight ah, sorry, mistake, my fault, v is perpendicular to force and dl is same direction with v, not force..
see ^ for justification
4 mins ago, by Abhas Kumar Sinha
@Knight no, $t$ isn't a vector first, and any equation in the form of $$ \vec a = c \vec d $$, then $ \vec a $ and $\vec d$ are in same direction..
 
But $dl$ should be taken in direction of force because as soon the force is applied it gets moved towars it
 
@Knight Do I need to draw to show you? I think you'll get better...
@Knight towards it? Who said that?
 
I
 
@Knight no, lorentz force is perpendicular, hence, it should be taken perpendicular in direction of v not, F
 
2:51 PM
@PM2Ring, hi, at least you know, me and a s a teenager I make mistake. But can you answer my question.
 
@Knight I guess that you don't understand the part, why $dl = v \, dt$?
^Why l and V are in same direction? @Knight If that is your question...
 
The reverse one. @PM2Ring
 
2
Q: Completely changing a question vs asking a new question

DaleWhen a OP has one of their questions closed one of the main desirable outcomes is for the OP to edit the question to address the issues that led to the closure. However, where should we draw the line between editing an existing question and asking a new question? In this case How light wave ha...

 
I am trying to solve the Schrodinger equation for the harmonic oscillator potential. I don't see why I should use the asymptotic method(physics.stackexchange.com/questions/501156/…) rather than directly writing the wavefunction as a power series(I tried that but I can't seem to get to the Hermite polynomial solution). Any thoughts?
 
@user199721 You can directly do it using power series in some cases, but it must terminate somewhere, that's the problem...
 
3:04 PM
well, it should terminate so that it is normalisable, right?
 
@Knight Yes, at the moment
dl is not the direction of the force in what you are discussing
dl is along the path of the particle.
If dl was in the direction of the force then all forces would do positive work all of the time.
I would suggest looking up the definition of work, and how to calculate it using line integral
 
@AaronStevens yes, why $dl$ is taken to be in the direction of the previous velocity (velocity before the force acted)
 
@Knight I don't understand why you think that. dl is just along the path the particle travels on, which is parallel to the velocity at all times.
 
@yuvrajsingh Which question?
 
@AaronStevens Because he has repelced $dl$ with $v dt$
 
3:11 PM
@PM2Ring give me minute let me write it.
 
@Knight See it algebrically, not physically...
 
@Knight Because the definition of velocity is dl/dt
 
@AaronStevens Both. The aliens in Incandescence went from a kind of Aristotelian physics straight to GR.
 
@AaronStevens but that dl is implied to be in the direction of $v$
 
@PM2Ring Is that a fiction?
@Knight yes
 
3:14 PM
@AbhasKumarSinha Wouldn't the direction of velocity will change as $F$ gonna act on it?
 
@Knight There was no direction of velocity in that sense before F
It happened just the moment F acted.
 
@AbhasKumarSinha Yes. By Greg Egan, who writes very "hard" science fiction. He's also good at non-fiction science writing, eg gregegan.net/FOUNDATIONS
 
Everyone see this - beebom.com/ratan-tata-teaches-you-how-pitch-your-startup Ratan Tata using Instagram to give startup lessons.
 
@AbhasKumarSinha Force acted perpendicular to velocity.
 
@PM2Ring like that surely joking of Feynman?
@Knight ugh! Then what's the problem?
 
user439435
3:17 PM
@Knight I think the sole reason for the confusion is that the magnetic force curves the path of the particle and hence the $dl$ shouldn't be in the direction of $v dt$ right? But you might notice that velocity (magnitude) doesn't change in due process and hence you can equate the magnitude of velocity times time as the path length.
 
@Knight Yes... by definition dl and v are in the same direction. Also by definition the work depends on dl. There isn't any assuming going on here. Just working with definitions of physical quantities
 
@user249451 I'm so glad that you have got me. Please explain from But you might notice that... .
 
@Knight Algebra doesn't changes even if electron moves in curvy direction...
 
@Knight dl is in the direction of v even if v is changing over time
 
@AaronStevens But, it's in an integral, so that doesn't matter and will remain perpendicular hence total work done is 00000
 
3:21 PM
@AaronStevens When force came into action the velocity would have come into the direction of force isn't it?
 
No. F=ma, not F=mv
 
@AbhasKumarSinha No, different to "Surely you must be joking, Mr Feynman". Greg Egan was a programmer before he was able to support himself through his science fiction. On his Web site, there are many articles about the science & mathematics that he uses in his stories.
 
@PM2Ring oh okay...
 
Throw a ball. The force is down, but the ball doesn't move straight down. It just accelerates down. It still keeps it's horizontal velocity
 
@AaronStevens Wouldn't acceleration gonna change the direction of velocity
@AaronStevens But eventually ball moves in the direction of force
 
3:23 PM
Yes it does. That doesn't mean the velocity is in the same direction of the force
 
@PM2Ring have you read - Mr. Tompkins by G Gamow..?
@Knight It's called electron, the small balls.
 
@Knight No. In the projectile example it always keeps it's horizontal velocity. It will never move exactly in the direction of the force
You are falling into a usual intro physics mistake that objects always move in the direction of forces.
 
@AaronStevens Doesn't it move downwards?
 
They only accelerate in the direction of forces
 
user439435
@Knight See if you take a look at any instant then $dl$ moved in that instant must have the direction of $v$. Now for calculating work what you need to know is the force as a function of displacement (for simplicity) and which in this case is always perpendicular to the displacement and hence is doing no work.
 
3:25 PM
It gains a downward velocity component, yes. But it doesn't start moving straight down
 
@AbhasKumarSinha I don't think so, although I've read about it in various places. I did read Gamow's One Two Three... Infinity, 20 or 30 years ago.
 
@PM2Ring My teacher gifted my Gamov's wonderland - arvindguptatoys.com/arvindgupta/tompkins.pdf It's very interesting, you will surely enjoy that..
 
@AbhasKumarSinha Thanks!
 
@PM2Ring :)
 
@user249451 When force was applied the velocity would be having some component in the direction of the force and hence should be the dl?
 
3:32 PM
@Knight Yes, the direction of dl will change. However the magnetic force also changes direction due to this. The magnetic force is special in that it's direction depends on the velocity of the particle. I suggest first making sure you understand work, differentials etc. for easier forces. Then you can look at magnetic forces
 
Hello everyatoms
 
@PM2Ring, how light produce heating effects.
 
user439435
@Knight No the instant velocity changes it's direction so does the magnetic force and hence never being parallel to the displacement.
 
Is this because two oscillating field,
Why only light save have heating effect, why not the wave like sound wave?. @PM2Ring
 
@NovaliumCompany hello
 
3:37 PM
@AbhasKumarSinha watcho daing?
 
@NovaliumCompany studying
...
 
f*cking school eh?
 
@NovaliumCompany yes bro... life sucks
 
user439435
@yuvrajsingh though sound waves does generate heat wtamu.edu/~cbaird/sq/mobile/2015/11/05/…
 
@yuvrajsingh sound waves also have heating effectg...
 
3:39 PM
here's a beat to cheer you up
 
@NovaliumCompany uh! Not my kind of music...
 
Pretty cool, recently I get to know, sound wave has heating effects. But threat are not significant.
 
@NovaliumCompany see the last verse
 
... nope
 
3:41 PM
I'm f****** dead! XD LOL LAMO LAMFO!!
@NovaliumCompany What is that very creepy thing...
 
@AbhasKumarSinha i just typed indian music :P
 
sorcery?
 
@yuvrajsingh You know how electromagnetic waves can be absorbed, reflected and emitted by objects?
 
@NovaliumCompany That guy seems chinese and it's not Indian....
music I mean^
 
@j Mac yes.
 
3:44 PM
@NovaliumCompany comments are spanish btw...
 
AAAAAA CAVENIAAA BARABICIRARAAAAAA
Nants ingonyama bagithi Baba
Sithi uhm ingonyama
 
@NovaliumCompany ukhuluma ngani
 
@yuvrajsingh en.wikipedia.org/wiki/Thermal_radiation Right, so there's the idea of thermal radiation. All bodies can emit and absorb electromagnetic radiation. It varies depending on the object and wavelegnth. If an object is absorbing more radiation than it emits to it's surroundings that heats the object up.
 
@NovaliumCompany How do you know that language? (zulu probably)
 
i google.
 
3:48 PM
@NovaliumCompany why zulu? you know it?
 
@yuvrajsingh en.wikipedia.org/wiki/Thermal_radiation#Interchange_of_energy Wikipedia goes into a lot of detail about the specifics of how it all happens
 
@AbhasKumarSinha I GOOGLED THE LYRICS!
 
@NovaliumCompany oh okay...
 
sory just pissed of from annoying programming error
 
@NovaliumCompany that guy seemed rather chinese to me... than zulu
@NovaliumCompany screenshot
 
3:53 PM
@AbhasKumarSinha it's secret
plus i have a brother programmer
 
@NovaliumCompany heheheh.......
@NovaliumCompany brother? yours?
 
have u seen elon musk roblox car?
@AbhasKumarSinha ye
 
@NovaliumCompany That one, which i used to draw back in kindergarden...?
@NovaliumCompany k
 
the cybertruck looks rather weird to me, donno
 
@NovaliumCompany #metoo
 
3:56 PM
Hi to all.
 
@ConstantineBlack Hi from all
 
Anyone remembers what is meant by γ=d(log a)/d(log b) where d is a differential
:)
 
Hi! Is anyone up for answering a question about two port resistor circuits?
 
@ConstantineBlack It means using chain rule $$ \dfrac{d \log a}{d \log b} = \dfrac{\dfrac{d \log a}{a}}{\dfrac{d \log b}{a}} $$
 
@AbhasKumarSinha
Thanks
 
3:58 PM
@ConstantineBlack :)
@NikolaPetrovic question?
 
@AbhasKumarSinha
Is there a way to send an image in this chat?
I've got a diagram of a two port RC circuit with some initial conditions that I think is impossible
 
@NikolaPetrovic Click upload button on the left side of the text box of the chat...
@NikolaPetrovic upload in imgur.com/upload and send links here
 
user439435
@AaronStevens can you answer this question of mine physics.stackexchange.com/q/519694/238497
 
Thank you @AbhasKumarSinha, one second
 
@NikolaPetrovic np
@user249451 At higher depth, more collision per unit area...
@user249451 You know statistical mechanics?
 
4:04 PM
@AbhasKumarSinha https://i.stack.imgur.com/Q7hLf.png This is a diagram of a two port circuit that allegedly has the initial conditions as depicted.
From this I am to find R1 and R6 so that I may find the value of I1 when I change the EMS generator output.

I've used the reciprocity theorem to swap E1,E2 and E3 so that I may get additional equations to solve the system for R1 and R6, but I find every system to be singular. I.e. I can't find any two R1 and R6 that satisfy these initial conditions.
 
@yuvrajsingh JMac has given you some good links, but also see en.wikipedia.org/wiki/Black-body_radiation The basic idea is that when a body absorbs light, the energy from that light isn't destroyed, because energy is always conserved. So that energy increases the kinetic energy of the atoms and molecules in the body, and that means its temperature rises. But that's just a rough description!
 
@NikolaPetrovic sorry what those arrows depict?
diodes?
 
@AbhasKumarSinha those arrows depict the measured current in the direction shown. I apologize for not using the symbol of an ampmeter
 
@NikolaPetrovic Apologies, I don't remember reprocity theorem, You may choose to wait for a while, till someone who knows comes here, or alternatively, you can use SE for it.
 
4:08 PM
I've also used a circuit simulator to recreate the circuit (i.stack.imgur.com/LL3ca.png) and it doesn't seem to me that any values of R1 and R6 will let me measure 140mA and 100mA as depicted
I recreated only the initial conditions with that circuit - the generators V3 and V2 I've replaced with a short-circuit
 
@NikolaPetrovic why not try circuitlab? I
 
@AbhasKumarSinha thank you for you willingness to help
 
@NikolaPetrovic No problem :)
 
@AbhasKumarSinha How do you believe circuitlab would help me?
I used EverCircuit to make that last one
 
@NikolaPetrovic Use simulators there to make charts and use Kerchoff's laws to roll the current to get the values and caluclate emp values of generators.
 
4:11 PM
I'm looping through a multidimensional dictionary in python (it has products with ids, names, prices...) and then I'm putting that information of each product in an excel file with code. The problem is I have duplicate products and I want to remove them, that's why before the loop, I create an array where I append the id of a product if it doesn't exist and if it exists I don't put it in the excel. It doesn't work :(. Like, I can print the ids of the products that repeat but it doesn't stop
them from being added to the excel file :(
 
@NikolaPetrovic That's good one too. I personally prefer qucs...
 
@AbhasKumarSinha I'll give it a shot :^D
@NovaliumCompany I believe I could help
 
@NikolaPetrovic You may try. But, I'm afraid, that's not my area, hence, I may fail to give you answers...
 
@NikolaPetrovic pliz
 
Sorry sir I have some doubts but due to lack of time, I need to go. @PM2Ring, so I come with my doubts tommorow.
 
4:13 PM
@NovaliumCompany how would you like me to help you? process the data for you or check your code?
 
@yuvrajsingh Ok.
 
@NovaliumCompany Nov try this one - hackerearth.com/challenges/hackathon/…
Very hard challange btw...
 
@NikolaPetrovic tell me things to check I guess :P
 
@NovaliumCompany code
 
@NovaliumCompany are you sure you have your If statement right for checking whether the id exists in the dictionary?
 
4:15 PM
@AbhasKumarSinha I can't. It's private I can't share it
 
@NovaliumCompany join me, we'll share prizes if we won... :P
 
@NikolaPetrovic if mystring in myarray:
@AbhasKumarSinha u'll join?
 
@NovaliumCompany Yes,
 
shouldnt it be
 
@NovaliumCompany Prizes may be small amount, but no hard in winning...
 
4:16 PM
not ( if mystring in my array):
if you want to append only when the product doesnt exist
 
@NovaliumCompany You could ask about that in the Python room, but we'll need to see some code, ideally a Minimal, Reproducible Example
 
i.e. negate the if statement condition
btw @NovaliumCompany, id suggest using windows powershell for that sort of processing
 
@NovaliumCompany BTW, to test duplicate products, it's probably more efficient to use a set (or maybe a dict), not a list. Especially if there are lots of products. Membership testing of sets & dicts is much more efficient than for lists.
 
it still doesn't work? @NovaliumCompany
 
4:23 PM
ye :(
 
that looks like it should work - the logic is fine
 
can you debug the code?
check if ids_array is being changed by the append
 
I tried to print the ids that are duplicates and it printss them
 
but it still adds the duplicates?
 
4:26 PM
yes
 
@PM2Ring sets are my recently new favorite data structure...they're so handy!
 
I have an idea to try
 
do you have your indendation done correctly after that? @NovaliumCompany
 
I'll just try to debug it a bit more
 
everything in your else statement should be indented as in lines 8 and 9
if you dont have an indent, its possible that its considering the code below the else statement to not be part of the else statement
 
4:28 PM
it's indented properly I believe
I'll try to debug
 
let me know whats up
 
oks :)
i'm hosting from pythonanywhere and not only did I pay for hosting but now they are telling me I can only use the CPU max speed only 2000 secs, WOW!....
 
debugging is always the best thing to do
just manually iterate through the code a few times and youll see what the problem is
 
@NikolaPetrovic :thumbs_up:
 
@NovaliumCompany That code looks ok, so I suppose the cause of your problem is in some other part of your code. BTW, if you do want to ask about this on Stack Overflow or in the Python room please post your code as (properly formatted) text, not as an image. People want to see code that they can edit & run, you can't easily do that with an image. ;)
@NovaliumCompany There's a free online Python interpreter at repl.it/@enaard/Python-3 It's ok, but a bit annoying to use from a phone.
 
5:11 PM
If I have a list of the products and I want to remove the duplicate products in that list based on the id, how do I do that. I get the id by mylist[i].find("id").text
OMGGG F*CKING HELP MEEEEE :(((((
i'm sdying
SHITTY CODE
AAAAAAAGHGHGHG
 
@NovaliumCompany How big is the list, usually? Removing items from lists is a bit inefficient. It's generally better to create a new list containing the stuff you want to keep. Do you need to preserve the order of the products in the list, or is it ok if they get jumbled up a little?
 
@PM2Ring I actually debugged the code and it turns out, with or without the duplicate removal thing, it still ends up adding everything. :(((9
 
Also, removing stuff from a list that you're looping over is generally a bad idea, unless you're very careful. It's a bit like sawing off a tree branch that you're sitting on... :)
 
Are you familiar with dictionaries? A decent way may be a dictionary with IDs as keys.
 
it's quite complicated. The products list contains beautifulsoup things where you can .text them or go further into the tree.
If I could remove the duplicates of the products list based on one of the list's parameters (id) where I get to it by doing .find
the past 3 hours of my life HAVE GONE TO FUCKING WAASTE$ DGHseyirtfgvb4784
 
5:23 PM
@NovaliumCompany Ok. So you've messed up the logic somewhere. And maybe some of that Beautiful Soup stuff doesn't work exactly the way you think it does. So you need to try & isolate the problem, like that page (that I linked a while ago) about minimal reprex & MCVE says.
 
I HAVE AN IDEA!
 
@NovaliumCompany Yeah, if you're angry it's hard to think straight. So take a break. And when you come back to your code, try something else, like putting your products into a dict.
 
i'm hungry, I think that's w hy I'm mostly angry
anyways i'm trying something now, hope it works #bless
 
Take a break to eat if you're hungry. Sometimes you do that and get back to magically realize the solution. And 3 hours haven't gone to waste -- they've been spent learning something that will save you time in the future!
 
I now made an array containing only the allowed ids (i.e contains all except the duplicates) and in the main loop I check if the product id is in the array of allowed_ids only if it it's in, then add and it still doesn't work..........
I'mma eat and watch a movie
 
vzn
5:44 PM
@AbhasKumarSinha interesting article/ pov but it sometimes pushes it too far (reflecting Blairs ideology). global warming as "einsteinian" vs not newtonian? lol!
> Tiny traces of carbon dioxide in the air make a heat blanket around earth because of the Einsteinian physics of photons interacting with CO2 molecules.
 
6:00 PM
I solved it!
GOD BLESS AMERICA
it's actually the logic that's the problem
it's quite complicated to explain but basically the allowed_ids array contains all ids except the duplicated but in the array there is one of each duplicate... it's a bit weird, anyways, time for Hawaii 5-0
 
user439435
6:25 PM
@AbhasKumarSinha sorry I haven't studied statistical mechanics yet(I'm a high schooler). Though if you have any relevant molecular model I can try to understand it(using whatsoever power of imagination that I have).
 
7:12 PM
About the issue, I fixed it. It turns out, I just tried the same thing I tried at the beginning and it worked. I have no idea why it works. lol
 

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