physics.qandaexchange.com/?qa=600/…

This question

@ACuriousMind I've only got two hats so far, and this was the funnier. I have to say it looks more like Father Christmas than a yeti :-)

Echoes in gravitational waves hint at a breakdown of Einstein's general relativity / sciencealert

After today I will be done with chemistry

forever

I will be free of this burden

Of all these magic numbers

and rote formulation

@Doraemonドラえもん I have a pretty insane Chemistry course

Search the chat history for multiple, long, dramatic, NSFW rants

@Doraemonドラえもん Yeah, I'm in Computer Engineering but I have a mandatory general chem course for my first semester

taught by a madman

The chemistry I study is the single stupidest subject ever

The prof hasn't written one thing on the board the whole year

apart from his sketches on ionic compounds which, to be honest, look more like a rorschach test than anything else

His professor is an idiot.

They were solving the Schrodinger equation in the first week.

Before we had even learned derivatives the man was trying to get us to do triple integrations on spherical coordinates

^

The prof has no idea how to teach.

He resembles an Oompa-Loompa from Willy Wonka's factory

That's my only consolation in this course

Already have, they don't care

@BernardoMeurer github.com/DanielSank/python-chat/tree/master/from-scratch

Chat server using my own event loop.

@DanielSank Cool!

I did some advancements on the rust version

then I had to study for exams

Now I have no clue what I was doing

haha

bitrot

I once got in a fight with my geography prof over knowing countries

I still remember all 250 flags

I won 5 bucks

@Doraemonドラえもん Thanks, I'll need it

@BernardoMeurer Isn't that common in physics?

We where using vector calculus in EM before the math class.

On the other hand, I saw courses with bad professors as challenges

@G.Bergeron I don't know about you but to me having even the slightest expectation that a freshman will be able to solve and comprehend Schrödingers equations in 3 dimensions using spherical coordinates is simply delusional

@BernardoMeurer When is freshman?

It's not a challenge like, say, Analysis which is a subject I find really hard but that I do enjoy sometimes

@G.Bergeron I started university less than 6 moths ago

I'm the freshest of the crops

And he did that on the first or second week of classes :)

@BernardoMeurer Ah ok, it's just that where I am we have this special thing between high school and university that lasts 2 years and is quite unique in the world.

So I get confused... We did spherical integral at that level, though but not alot of people knew what they where doing

In any case, don't you study multiple variable calculus in first year?

You did spherical integrals immediately after leaving High School?

No. No one does that as far as I know

@BernardoMeurer No, but then again we leave earlier

And then there is 2 years of what's called CEGEP

And finally 3 years of undergrad studies

I have Real Analysis in my first semester, than multivariable calc on the second semester, then I take complex analysis because I need that for circuit analysis or something

So 1 year uni for us is like almost second year uni elsewhere

Spherical harmonics is in wave and optics class

first semester of second year

I have waves and optics on the 3rd or 4th semester i think

Next semester I have wave mechanics or w/e it's called

In any case, it's hard to compare... I mean in that cegep thing, you do classical mechanics, electromagnetism and wave/optics/special relativity even if you don't go in physics

It's for anybody doing science in general/engineering/medical degrees, etc.

And this means that we, physicists, have to do biology and chemistry at that level, which is half-way between the end of high-school and undergrad

Also, everybody does 1 variable calculus and linear algebra... When is that done in the US?

Somebody knows?

@MAFIA36790 CEGEP are a thing that only exists in one province in Canada. I haven't heard of something like that elsewhere...

People going to uni are mixed with people doing professional technical degrees. Everybody does a common core of French/English litterature, philosophy and a bunch of other stuff. Then, if you choose natural sciences, you do all that I mentionned.

@MAFIA36790 But yes it really does mean that future medical students have to compute relativistic time dilation and such at some point... :p

@MAFIA36790 He's trying to say he's a dirty french canadian :P

@BernardoMeurer And that they decided to have this oddity in education after high-school. I think the idea was to not have so strong a difference in people doing technical degrees vs people going at uni.

anyone there?

Find the equivalent resistance between A and B. plz tell the solution also

@ArmaGeddON gimme teh codez

codes?

(A) (B) (C) & (D) are 4 possible choices

What have you tried?

m totally confused, can't understand anything in that circuit

Nothing seems to be in series

yup infact thats all i know

@ArmaGeddON It's drawn in a way to confuse you. Your first task should be to draw it without any circuit lines crossing.

Then you can more clearly see which resistors are in series/in parallel and apply the usual formulae to solve the exercise

@ACuriousMind i tried but no cookie

I think YES

because same current isn't passing in consecutive resistors

just a sec, lets name them for convinience

looks good?

now i think, current starts from A.. then on the junction

divides into 3 parts

to Ra, Rd and D

Through D again divides to Rb And Rc

and then everything went to chaos

thanks for that

@ArmaGeddON Hint: You are allowed to shrink the lines with no resistor on them, i.e. A and D and C and B are really the same point

okies....

Which, by the way , is exactly what JohnRennie did there, he shrank the line between B and C.

still observing it

@dora

@Doraemonドラえもん so current to Rb goes through D?

with @JohnRennie's diagram i got the right answer but most of the time i won't be able to alter the circuit easily

YES I was right !! :D

:)

i will but next question kinda makes my insight go crazy

just a minute, labelling it

labeling*

First of all plz tell what the question means?

Does the question mean that if we pass a current from C and gets out from D, no resistance will be ovserved?

@ArmaGeddON The question makes no sense - if the ring has zero resistance, there is a path of zero resistance from A to B, hence the resistance between A and B is zero.

@Doraemonドラえもん Uh, where does it lie?

I still feel sad for TP.SE...

Never got to use it

There's no resistor between it and the ring so for all practical purposes it lies "on the ring" regardless of how inaccurate the drawing is.

A seems to be a floating point, right?

@G.Bergeron Then use this one instead! Nothing you could've asked at TP.SE is off-topic here, except homework-like questions.

@AccidentalFourierTransform Huh?

Ahhhh

That drawing is crap

There's no connection from A to the ring, got it.

Yes its (D) but i wonder

@ACuriousMind Yeah I'm just sceptical of the odds of a research/advanced question being answered here. I am gonna try. I said I will and I am thinking of what could be a good first.

@ArmaGeddON Try drawing the better diagram yourself this time, and remember that you are allowed to shrink the lines without resistors.

Combined (R1,R2,R4) and R3 arent in series, they're pretty in parallel