The h Bar

Secret

09:09

Sorry the previous one has a typo.

From this result one can see for this particular charged wire with current moving in the yz plane (that is, the wire as a whole is moving continously in the yz plane with some velocity), the continuity equation restrict the x component of the current as the total rate of change of the charge density with time for each unit of charge density at each point

This is a nonlocal effect because for each point on the wire, the x component of the velocity depends on the rate of change of the charge density on all points of the wire, and this change opposes (as in…

skill patrol

09:40

@Secret are you studying this for your own interests?

:-)

Danu

@0celo7 Guess why it's called the tangent function :P

Secret

@skillpatrol
I am, because that overthink problem I conceived 2 days ago because of of the wire on x axis question looks intriguring and I want to visualise how it moves

Secret

It is pretty common to see me ocassionally do algebra, calculations and some physics problems simply because I want to visualise them

skill patrol

Sounds like a good habit.

Secret

However, it can sometimes distract me from the real work I need to do, in this case I should have read those boring analytical chemsitry journal articles

The problem for me and some of my friends is that, while we like and passionate about science, once it get the label of "work and assignment" it feels boring to us and we start to procrastinate

Danu

09:45

@Secret Why are you doing this

Secret

@ Danu
Because I am curious on what this system look like:
$$\rho(t)=\lambda(x(t))\delta(y-r_{y0}(t))\delta(z-r_{z0}(t))$$
$$\mathbf{J}(t)=\rho(t)\mathbf{v}(t)$$
$$\mathbf{v}(t)=(v_x(t),v_y(t),v_z(t))^T$$
$$\mathbf{r}(t)=(x(t),y(t),z(t))^T$$

which is inspired from answering this question and part of my brain overthink the question and generate this system

http://physics.stackexchange.com/questions/209922/definition-of-a-line-charge-with-dirac-delta-function/209926#209926

Danu

That's not what I was takling about

I was talking about the

Secret

Line separator, else the wall of text will get too big

Arc676

n(people) > 0?

Secret

(cont.)
The more general case:
Charges and currents
$$\rho(t)=\lambda(x(t))\delta(y-r_{y0}(t))\delta(z-r_{z0}(t))$$
$$\mathbf{J}(t)=\rho(t)\mathbf{v}(t)$$
$$\mathbf{v}(t)=(v_x(t),v_y(t),v_z(t))^T$$
$$\mathbf{r}(t)=(x(t),y(t),z(t))^T$$

Continuity equation
$$\frac{\partial \rho}{\partial t}+\nabla\cdot \mathbf{J}=0$$

For $\lambda (x) \neq 0$ (since for values x where lambda vanishes the equation is the trivial 0=0 which is always true), $v_x$ must be of the form:

$$\dot{\lambda}(x)=-\frac{d\lambda(x)}{dx}v_x$$

Danu

10:03

@Arc676 Possibly

Arc676

n(people) = 10 apparently

Danu

Not really

Secret

1. The reason of the absence of y and z dependencies is because you can always transform into the centre of mass frame of the wire thus the wire will then be stationary in y and z (which the workings have already been shown in the first set of calculations)

2. The motion of the charge density forms a wire. As the wire move around in the yz plane, the nonuniform charge density of the wire varies

The continuity equation told us in this system, the current in the wire is contributed by the time dependence of the charge density, since $v_x$ depends on $\lambda$

Arc676

well people in the room

not necessarily active

I asked yesterday if there is such thing as a polarizer that only works in the presence of a magnetic field. Does this exist?

Danu

@Arc676 No idea.

Arc676

10:07

To Google!

Danu

what does that even mean

Secret

the charges at each point of the wire is interacting strongly in the wire even if they are extremely far away

It is unsure how to interpret this

Danu

EM waves must always have magnetic and electric components

the two are inseparable

Arc676

@Danu [go] to [search] google

Danu

@Arc676 I meant your earlier question

Arc676

10:12

Oh.

I remember in a documentary about Faraday he discovered some type of material that only polarized light when in the presence of a magnetic field

Essentially, you use a detector that only responds to light with a certain polarisation, aim it at light of a different polarisation, and this material (if in the presence of a magnetic field) polarises the light

Danu

ah, you mean as in a "background field"

I was talking about the wave itself

Arc676

right

Secret

to be done later, must get back to chemistry assignments

Arc676

Do you have any ideas?

Danu

@Arc676 No, but it seems pretty likely that it exists

Arc676

10:26

Alright

yuggib

worst set of labels ever?

0

Q: general procedure for determining whether the choice of origin is arbitrary

Please give a general procedure for determining whether the choice of origin is arbitrary, or give relevant references (if not in general, then if possible for elastodynamic scattering in Cartesian coordinates). Thank you.

Danu

@yuggib edited.

skill patrol

lol

Arc676

10:42

labels as in tags right?

skill patrol

Thank you @yuggib for immortalizing that post here in chat :-D

yuggib

:-D

@Arc676 yep

Arc676

new tags definitely better

given how different the original tags are, I wonder how the OP would have tagged the question if there wasn't a tag limit

ACuriousMind

13:05

@DanielSank Yes.

skill patrol

but why?

0celo7

Damn, we lost

Well my life has no meaning now

Huy

sory

ACuriousMind

@skillpatrol Examples: 1. The question shows little research effort, but does not lack it so blatantly that I'd VTC. 2. The question asks about the meaning of an equation in some paper, and anyone even remotely familiar with the topic the paper is about would know it. Not a useful question because it is a question you can only ask if you are not at all equipped to understand the topic at hand, but doesn't fall under any close reason.

3. The question is clearly (to me) intended to promote some non-mainstream view (making it not useful), but phrases it in a way that is technically on-topic.

I'm sure I can come up with more

0celo7

@Huy are you Canadian

Huy

13:11

no lol

but sory

so wheres ur pics @0celo7

0celo7

My roommate has not left the room in two days :O

Dunno what his deal is, usually I'm in here more than him

Huy

lol

or more like LoL

(gaming addiction is real)

0celo7

::feels urge to play R6V2::

ACuriousMind

...why would anyone begin a question with "Sir, [question]"?!

Huy

13:27

maybe if they think you're a knight

ACuriousMind

Do they perceive physics.SE as a single English gentleman or what?

0celo7

NOW THAT PERSON IS SHOWING SOME RESPECT

Ffs can we have more people like that please

Oh that gets my aristocratic juices flowing

skill patrol

classy^

ACuriousMind

@0celo7 But...it's not respectful to address potentially female users as "Sir", is it?

I mean, you even write "Sir or Madam" in letters when you don't know the recipient.

0celo7

@ACuriousMind in the military, "Sir" is unisex

ACuriousMind

13:30

@0celo7 We are not in the military, however much you might wish it were so!

0celo7

Why does everyone think I want this to be the military

skill patrol

Third world countries use "Sir."

0celo7

Good for them

My department head is "Sir"

And before you get in a fit, I started calling Dr. Lang by his first name and my LATA by his first name

So I can be casual

It feels awkward, but it can be done

skill patrol

Approaching strangers with respect is a good idea.

0celo7

How do you expect me to call Denzler by his first name when he calls me "Herr Unger"

ACuriousMind

13:36

@0celo7 Who does? If they call you by your last name, you obviously call them by their last name, too!

0celo7

Exactly

I had a teacher in high school who called everyone by their last names

Although once he figured out a stupid nickname for me he started calling me that

My name is not good for nicknames

"Hungarian" comes to mind

ACuriousMind

Oooh, do tell us the stupid nickname!

0celo7

Rhino

skill patrol

wtf

ACuriousMind

@0celo7 ...why?

0celo7

13:40

Can you come up with a better nickname for Ryan

It's what my dad calls me, so maybe they had a chat...

skill patrol

Bryan?

0celo7

Maybe he let it slip during a parent teacher meeting

@skillpatrol that's stupid

There are people actually called that

skill patrol

:(

0celo7

A good nickname is not a name

skill patrol

classic^

0celo7

13:42

Like "Lindsay McDonald" was "Eeyore"

Well that is a name

skill patrol

:-/

0celo7

But not a name you'd find in the average ensemble of people

"Maddie Causey" was "Causeway"

Why did someone star that

skill patrol

Nickname

A nickname is a shortened substitute for the proper name of a familiar person, place or thing, for affection or ridicule. The term hypocoristic is used to refer to a nickname of affection between those in love or with a close emotional bond, compared with a term of endearment. The term diminutive name refers to nicknames that convey smallness, hence something regarded with affection or familiarity (e.g., referring to children), or contempt. The distinction between the two is often blurred. It is a form of endearment and amusement. As a concept, it is distinct from both pseudonym and stage name...

0celo7

> Ah, the Middle East. Where in Syria the Russian and Iranian-backed dictator is fighting US-backed rebels, Saudi-backed rebels, al-Qaeda rebels, Kurdish rebels, and ISIS. ISIS is simultaneously fighting the US backed rebels, the Saudi-backed rebels, the al-Qaeda rebels, and the Kurdish rebels.

Meanwhile, Iraq, which is a ??? in terms of democracy standards, is fighting ISIS, while somehow being allied with both the US and Iran.

In Yemen, Iran is backing the Houthi rebels, while Saudi Arabia is invading and bombing on behalf of the US and Saudi-backed dictator, who has lost his capital bu…

Now that's star worthy

skill patrol

people killing each other is star worthy?

0celo7

13:50

It's informative

skill patrol

meh

0celo7

Time to get out the iPad

skill patrol

with 9.02?

0celo7

@Danu Wrong theta, that's the problem

No

I want to see the star wall

@ACuriousMind pls link to the sir question

ACuriousMind

@0celo7 Why? I edited it because the grammar was abysmal, the "sir" is gone.

0celo7

14:02

Pls

1

Q: specific heat of water and ice

We know that denser objects have lower specific heat capacity. Since water is more dense than ice, water must have lower specific heat capacity than ice but we know that water's heat capacity is $4.200\,\text{J/(gK)}$ and ice's specific heat is $2.100\,\text{J/(gk)}$. Why is this apparently the ...

thermodynamics

Why didn't you just tell me :(

HAHA

He put sir in his other question too

Man's a boss

0celo7

14:38

Chat ded

Huy

sory

0celo7

15:07

Stop being Canadian

@Huy what multiplayer games do you play on PC

Huy

hearthstone

apart from that atm none

dont have time for games im an adult

0celo7

Uh-Huh

Huy

when I have time I prefer Cities Skylines

I secretly want to become a city builder

ACuriousMind

I'm so glad I'm not an adult, apparently

Huy

and an architect

but I wouldn't dare study any of it because job opportunities are not very good

I used to play Civ

but then I decided it was high time I went to bed again

ACuriousMind

15:17

@0celo7 Too slow.

Huy

and ofc FIFA but that's on my PS4

0celo7

I didn't post that with the intention of deleting.

I figured it was a bit much.

Huy

y u ask

u bored?

0celo7

I want to vidya with you...

ACM refuses

Huy

lel

0celo7

15:19

He's all about them Kerbals

Huy

well I'm all about them Cities atm

ACuriousMind

No, currently I'm replaying Witcher 3

0celo7

Isn't that a multi dozen hour game

ACuriousMind

Yes, it took me 82 hours the first time.

0celo7

Ok I'm not doing anything until 3

@Huy get BF4

Huy

15:21

nah I don't like shooters

0celo7

Wtfffff

Huy

besides I still have my crappy keyboard atm

let's play LoL together

^w^

0celo7

Correlation: smart people dislike shooters

I like shooters :O

Huy

I'm sory

0celo7

And you don't have GTA for PC

Huy

15:22

why would I buy it again

I already bought it for PS3 and then PS4

with no discount

there should be a discount for the PC version if you already got another version

0celo7

We could get that Skyrim mod that allows for online play

MxR just did a video on it, it's really coming along

Huy

skyrim is boring

I only play it for the graphics

0celo7

I want that German Skyrim hack to come out

@Huy why

Huy

because it looks good

I get bored at RPGs very quickly

I have like 200 of them but never played any

0celo7

And you don't have Splinter Cell Blacklist I assume

Huy

15:25

nop

ACuriousMind

@0celo7 Enderal will be glorious

0celo7

@ACuriousMind RIP frame rate, the trailer looks cluttered as hell

But awesome

And Fallout 4. I bet you won't see much of @ACuriousMind and me the week that comes out ;)

@Huy any Tom Clancy games?

ACuriousMind

@0celo7 Confirmed.

Huy

idk

0celo7

Work with me here

Huy

15:28

steamcommunity.com/id/huy227/games/?tab=all @0celo7

0celo7

GTA4

Let's do this shit.

Huy

dude I got my keyboard for toddlers

I can't do shit on this keyboard

you gotta wait at least till tomorrow

0celo7

Fuck I bet my roommate is still asleep

Huy

I'll get a new one tomorrow

0celo7

Dude I used my Apple keyboard for a while and it worked just fine

Huy

15:30

what do you mean by for a while

when

?

0celo7

Why do you have so many unplayed games

Huy

I played

"I have like 200 of them but never played any"

that doesn't just apply to RPGs

0celo7

Also how do you have that many hours on sleeping dogs

Huy

my brother played it too

I had the good PC

0celo7

Huh

I have 14, you have 60

Huy

15:32

are you at 100%?

0celo7

Ah

Actually, I don't think I finished the cop missions now that you mention it

Huy

also I sometimes just goof around for like hours

0celo7

I'm so salty I can't play TW3

Huy

cuz I'm bored but don't wanna do story

0celo7

Freaking Apple

Huy

15:34

I'm so salty I'm still sick

since last weekend

0celo7

Make better drivers for you shit

Huy

-.-

0celo7

I've been sick for a month

Huy

y

0celo7

Bronchitis. Ain't nobody got time for that.

Huy

15:35

can't you get some inhaler or so similar to asthma?

0celo7

::wonders if Europeans get the reference::

@Huy I got antibiotics

Which helped

Huy

but

ah

0celo7

But I'm still coughing up random crap

My sinus infection cleared right up at least

Dude can you gift me some of your games

Can you even do that

Huy

no but maybe in future

I started buying them as a gift instead of directly

and then if I decide I want to play it I can just gift it to myself

and else I'll just gift it away after some time

0celo7

I want the FEAR games

Huy

15:38

I got them at humblebundle or some steam sale

0celo7

Too much money for me

I live in squalor ;_;

My phone is two years old

::sobs::

Huy

mine one

looking forward to iPhone 7

0celo7

Not sure if I'll even get a 6s

Huy

I don't

because I have the 6

0celo7

You should rap about how rich you are

Huy

15:42

sorry I don't rap

also I'm not rich yet

maybe in 2-3 years

0celo7

ACM doesn't even have food and all you do is flaunt your wealth

Huy

then I'll buy a Tesla Model 3

0celo7

Cost of living can't be that bad in Switzerland if you're buying a $80k car straight out of college

Huy

how do you know it'll be 80k

skill patrol

:O

Huy

15:44

rumours is at 30k

0celo7

Thought Teslas were luxury

Huy

and I can probably get a used one from some rich guy who wants the newest model and sells the old one

the Model 3 will be presented in 2016 and is supposed to be around 30k

so more people can afford them

the Model S so far was around 80k

0celo7

When I have some money, it's all about that MB C class

Huy

I won't buy a MB before I'm at least 50

0celo7

C class is pretty affordable

Huy

15:46

it's not about the money

it's about the MB

MB is for old people

imo

0celo7

Your opinion is wrong and so are you

Huy

sory

0celo7

You know what's sad

ACM is living in starvation and can't drive either

Huy

why

0celo7

Because he's starving!!

Huy

15:48

aha?

0celo7

Some German thing

Huy

ok

0celo7

Probably thinks cars are evil

Huy

:(

0celo7

Roommate still sleeping

skill patrol

15:52

do you talk to him?

0celo7

Sometimes

skill patrol

does he go to the games?

0celo7

Neither of us went yesterday

@Huy he sees no need to know how to drive

skill patrol

hi @obe

Huy

ic

I do

0celo7

15:57

@obe problem set

obe

hey

working on it.

0celo7

It was due last week!

obe

well fml.

0celo7

My mental image of JD is morphing into DJT

skill patrol

0celo7

16:08

cnn.com/2015/10/01/politics/benjamin-netanyahu-obama-iran-u-n-/…

Wow

Watch the video

Huy

配信者が配信中にオイルマッチで火事になる大事態に 2015年10月4日

►

Wow

Watch the video

0celo7

That you?

Huy

yes

apparently that was on stream

on accident

0celo7

What the fuck

Huy

right
?

0celo7

16:18

What is that girl in the background

Huy

probably some program automatically reading viewer's messages on twitch or so

0celo7

Lol

Huy

ikr

apparently the fire burned down 3 more flats

uhm

apartment buildings I mean

0celo7

Lol he should have used the box at the start

skill patrol

bizzarre

Danu

16:27

I'm just asking a method of finding the coupling coefficient other than the formula given.whether it be using flux, magnetic field etc. — Prachurjya Biswas 1 min ago

I'm giving up

Huy

y u give up son

0celo7

Don't jump

Huy

let's play some Cities Sklyines @0celo7

I'm bored

0celo7

How much is it

Why not GTA 4

lemme add you on Steam

what's your name

too many Huys

@Huy add revolver_0celo7

$15 :O

Huy

16:49

it's on sale 50%

also it doesn't have multiplayer :D

0celo7

wow you punk

Huy

lol

so mad

0celo7

not mad

just sad

Huy

sory

0celo7

so my roommate is still asleep

Huy

16:52

yeah

typical LoL gamer behaviour

my LoL friends would play until 4,5,6 am and get up around 1,2 pm

0celo7

yeah

isn't that what @ACuriousMind does?

Huy

you know him better

0celo7

dude just get Bf4

Huy

I don't like shooters

0celo7

I promise it's a good shooter

it's good tho

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