The h Bar

0celo7

00:29

@ACuriousMind I forgot, happy b day

ACuriousMind

@0celo7 Thanks :)

0celo7

@ACuriousMind shouldn't you be drunk right now

Or maybe you are ;)

ACuriousMind

I drank a bit from the Laphroaig my parents sent me, but I've got the whole day to get drunk ahead of me ;)

0celo7

@ACuriousMind As a birthday present, wanna help me solve the wave equation on a 90 degree wedge of a disk with Dirichlet boundary conditions...

ACuriousMind

@0celo7 hell, no

0celo7

00:43

@ACuriousMind tfw this is only a third of my homework...

these PDE problem sets are stupidly long

half the time is spent figuring out the completely disorganized lecture notes

I think the prof has ADD

his answer to "what the hell are Bessel functions" was "think of them like sine and cosine"

@ACuriousMind there exists a 700 page book on Bessel functions...

dmckee

@0celo7 Never miss the chance to link

Last week, we busted the myth that electroweak gauge symmetry is broken by the Higgs mechanism. We'll also examine the existence of God and whether true love exists.

and

0celo7

01:01

> most beautiful, deepest result in theoretical physics

really

I think $G_{\mu\nu}=T_{\mu\nu}$ is better

althought the deepest might be the M theory lagrangian

whatever it is

ACuriousMind

Those are not results, those are specific theories

The beauty of Noether's theorem lies precisely in its universality

0celo7

@ACuriousMind Noether's theroem is just about finding first integrals of an ODE

ACuriousMind

@0celo7 The equations of motion of a field theory are typically not an ODE.

0celo7

@ACuriousMind PDE

same thing

:P

Arnold has tainted me

He present's Noether's theorem as:

here is a useful method for finding first integrals of Eq. something

$$g(r,\theta)=\sum_{m=1}^\infty\sum_{n=1}^\infty A_{mn}J_{2m}(\alpha_{mn}r)\sin(2m\theta)$$

Will pay well for a formula for $A_{mn}$

0celo7

01:24

@ACuriousMind How does $$A_{mn}=\frac{4}{\pi}\frac{\int_0^a \int_0^{\pi/2}rJ_{2m}(\alpha_{mn}r)\sin(2m\theta)\mathrm{d}\theta\mathrm{d}r}{\i‌nt_0^a r[J_{2m}(\alpha_{mn}r)]^2\mathrm{d}r}$$ look

ACuriousMind

horrible

0celo7

@ACuriousMind I need your EM skills :(

@ACuriousMind Ok i guess that was a bit of an unfocused question :P

-1

A: Stokes theorem in Lorentzian manifolds

in order to apply the stokes theorem to Lorentz manifold we must take normals at the boundary ... The general stokes theorem for differential forms is valid for any orientable manifold with a boundary: $$\int_D d\omega = \int_{\partial D} \omega$$ A metric is not req'd; so is valid for...

Who gave that an upvote

He literally copied from the book

And didn't even answer the question

0celo7

02:09

@dmckee If a wave goes through a cord with a variable mass density, why is the frequency constant throughout?

dmckee

Two ways to think of this:

(a) What would happen at a point where the frequency on the left was different from that on the right? The cord would have to be discontinuous most of the time.

(b) Each part of the cord is a driven oscillator. In the steady state, driven oscillators take on the driving frequency, not their natural frequency.

0celo7

@dmckee Hmm.

I'd need to see (a) to be convinced

I can't picture it

(b) works for me I guess

0celo7

03:06

@FenderLesPaul solutions

Bernard Meurer

Heyo

0celo7

03:22

@BernardMeurer GTA?

Bernard Meurer

@0celo7 Nah I'm in a mood

0celo7

huh?

Bernard Meurer

03:44

What's a Pepsi Max?

0celo7

@BernardMeurer never heard of it

DanielSank

04:53

Wow, a soft question that's not entirely terrible:

1

Q: What is the "single equation" in string theory that's an inch long?

Michio Kaku, famous theoretical physicist claims to be one of the founders of string field theory and to have contributed a equation that's "no bigger than your thumb" that ties general relativity and quantum field theory together. What is this equation I keep hearing about and why is it important?

0celo7

@DanielSank hello

DanielSank

05:10

yo

@0celo7 You want something?

0celo7

@DanielSank no, I was just saying hi

DanielSank

@0celo7 hi

0celo7

@DanielSank did you read my proof

DanielSank

@0celo7 Nope.

0celo7

are you at work right now

DanielSank

05:18

@0celo7 Nope.

0celo7

then please do

DanielSank

@0celo7 Dude, I have no idea what you're talking about.

Am I supposed to magically know where to find said proof?

0celo7

uh-huh

second to last post I've made

DanielSank

On P.SE?

Bernard Meurer

Yeah

0celo7

05:20

@DanielSank yes

Bernard Meurer

He's like a Jeovahs Witness with his proof

knocking from mention to mention

DanielSank

@BernardMeurer I looked at @0celo7's penultimate Physics SE question. It's a bunch of stuff I don't understand.

0celo7

@BernardMeurer did you read it

@DanielSank question or answer?

DanielSank

@0celo7 Question.

0celo7

@DanielSank answer bruh, not the question

IQヴィーナス～天才JK日本一決定戦～ 12月30日

►

This randomly started playing while watching YouTube...

Bernard Meurer

05:23

@0celo7 Dude I can't even understand my little pony right, let alone that sorcery of yours

@DanielSank I feel you there

DanielSank

@0celo7 Understanding that would take work on my end. A lot of work.

Not gunna do it. Sorry.

0celo7

@DanielSank wth I tried to make it easy to read

DanielSank

@0celo7 ok

I will write an "easy to read" treatise on signal processing. Would that be easy for you to review?

0celo7

@DanielSank so you're telling me it's hard to read?

@DanielSank probably

DanielSank

@0celo7 There's no objective scale, man.

This stuff isn't my bread and butter.

Bernard Meurer

05:25

@DanielSank An easy to read paper on signal processing has been written, it's called the bible

0celo7

the bible is pretty damn hard to read

Bernard Meurer

I found it pretty okay

Didn't read it through though, too big

DanielSank

@BernardMeurer Huh?

Bernard Meurer

@DanielSank I'm in a mood, pretend it's real funny

No, don't that'd make me confused

0celo7

@BernardMeurer HA HA HA

HA

HAAAAAAA

DanielSank

05:30

@BernardMeurer Does "in a mood" mean "high"?

Bernard Meurer

@DanielSank No, it's more like I'm laying on the floor

and the mobile chat just makes me more pissed

DanielSank

@BernardMeurer on... the... floor... ok.

Bernard Meurer

@DanielSank It's the coldest place in the house right now

even the walls are warm

user507974

07:20

guys, i still stumble when I have to do things like this $$\frac{d}{d E\beta}(\frac{1}{E\beta^2})$$

what should I be doing here

its not like I can treat the excess $\beta$ as a constant right

hi @JokelaTurbine

in paricular my problem is form $$ \frac{d}{E\beta}ln(\frac{\alpha sinh(\beta E \mu)}{E\beta^2 \mu}) $$

I really wish there was a nice book to read that covered those weird little math tricks you see all over the place in physics

Slereah

08:54

I voted you up, though I answered Yes my self for the same Key question. Your points are so valid here. And my CTC is not as it's expected. But energy movement is generally a closed loop. Then String, time travel; I can only agree with you. — JokelaTurbine 10 hours ago

Help

innisfree

09:06

Has anyone tried this problem book? amazon.com/Problem-Book-Quantum-Field-Theory/dp/3540770135

It's pretty good, I worked through the beginning today

GPhys

The answers I see on this site never cease to amaze me physics.stackexchange.com/a/241134/10908

yuggib

09:22

@innisfree a problem book of physicist's QFT sounds like no fun...a lot of mindless boring calculations

nevertheless, it may be useful (?)

Slereah

You need to do the boring stuff, I'm afraid

Learning QFT is doing a lot of awful integrals

And doing all the operator shenanigans

yuggib

Bah, I learned that in QFT there were boring integrals and stuff

but let that be an S.E.P.

(and then ended up doing my master thesis on boring integrals and algebraic computations...but in worldline QM)

;-þ

Slereah

09:38

And GR is a lot of awful PDEs and integrals

I think I found a way to get lots of free points

1) Ask a question so complicated that nobody will be able to answer it

2) Put a bounty on it to get a lot of upvotes

3) Get the bounty points back

IT IS FOOLPROOF

Sidarth

ACuriousMind

10:18

Yay, I triggered the serial voting script by downvoting mindlessly copy-pasted answers.

Slereah

You naughty boy

ACuriousMind

If I hadn't already suspected that, I would now be very confused why there's a bunch of "undownvoted" in my rep history

The feedback one gets is really not very clear; if I didn't know about the reversal script, I'd think it's some bug

innisfree

@yuggib I skipped the most tedious looking questions, but did most of the first chapter on the Poincare group. A good refresher

Is this a lampoon? physics.stackexchange.com/questions/99549/gossip-in-physics

2

Q: Gossip in Physics

Given, $M_4 = \Sigma \times C$, How do you get an effective theory by studying maps $\Sigma \rightarrow M_4$ . Technically, the physics in one manifold is supposed to gossip about the overall affairs of people in the entire manifold at least up to a certain limit. To be direct I am...

quantum-field-theory supersymmetry

ACuriousMind

No idea, but the question is seriously unclear

Hari Prasad

10:46

@ACuriousMind Whst is UV/IR mixing?

user507974

@ACM hey how goes it

James C

good day all

yuggib

hya

James C

11:01

is it alright to ask about some book/resource recommendation here?

yuggib

yep

James C

great. i would like to know if there is any good basic physics textbook (college/university level), which does most of teaching through giving problems for the reader to solve, and then provide explanations through them and so

i hope you understand what i mean

yuggib

yes I understand, but personally I don't know of a book using such an approach

James C

i need a bit of a refresher or quick course through physics again. but i don't think i can now afford first reading a thick textbook on theory, and then do problem solving to properly master the material

alright

yuggib

so essentially you need a problem book with extended solutions/explanations

however maybe someone else here may know and answer ;-)

James C

11:06

yes that sounds ok. it doesn't need to be problems only, but still mainly focused on problems and teaching principles through solving them

i could ask a questoin on the SE, but i am very unsure if question would fit there

Physics Meta

0

Q: Incosistent policy on "homework" questions

Recently I asked a question on physics stack exchange. It was closed with a reference to faq guidelines. Here is the question that was closed: Maximum period of a vertically spinning ball. Please note that while this was not a "homework" question, I can understand that it is classified as a hom...

discussion closed-questions homework close-reasons

yuggib

it seems that "Feynman's Tips on Physics: A Problem-Solving Supplement to the Feynman Lectures on Physics" may be roughly the type of text you are interested in

but I never read it so I don't know

it essentially contains exercises and solutions to the problems given by Feynman in his lectures

James C

ok, that's something to start from, thank you for sharing

user116211

@yuggib: o/

user116211

drvrm

194 6

quantum-mechanics newtonian-mechanics homework-and-exercises x-rays electromagnetic-radiation energy quantum-spin

user116211

11:16

Has anyone apart from ACM seen his plagiarised posts?

user116211

@user507974 (*￣m￣)

user507974

@user36790 howdy

user116211

@user507974: o/

user507974

what time is it your place anyways

user116211

@user507974 16:49

user507974

11:19

ok, so 13 hours ahead

oops

wait...

how is it 49?

@user36790 I've never heard of half time zones

user116211

@user507974 which country? wait.... you said it.

user116211

Indian Standard Time

Indian Standard Time (IST) is the time observed throughout India and Sri Lanka, with a time offset of UTC+05:30. India does not observe daylight saving time (DST) or other seasonal adjustments. In military and aviation time IST is designated E* ("Echo-Star"). Indian Standard Time is calculated on the basis of 82.5° E longitude, in Shankargarh Fort, Mirzapur (25.15°N 82.58°E / 25.15; 82.58) (in Mirzapur district in the state of Uttar Pradesh) which is nearly on the corresponding longitude reference line. In the tz database, it is represented by Asia/Kolkata. == History == After independence in...

user507974

interesting

yuggib

@user36790 howdy

user507974

i guess its actually 13 and half hours ahead

user116211

11:22

@user507974 you live in?

user507974

US doesnt do half time zones

user116211

US?

user507974

yep

yuggib

@user36790 plagiarism in SE seems quite absurd

user507974

@yuggib what do you guys mean by plaigarism

copying posts, pulling passages from other places and not citing?

user116211

11:23

@user507974 what is half-time zone?

yuggib

@user507974 I assumed the meaning was the standard one

user507974

@user36790 by that i mean time zones that are offset in any increment less than 1 hr

yuggib

no, I am meaning about plagiarism

user116211

@user507974: Enjoyed Super Tuesday?

user507974

@yuggib responded to the wrong one

user116211

11:25

@user507974 O.O

user507974

@user36790 eh...wasn't too surprised about it, kinda just waiting to hear stories about voting fraud

yuggib

@user36790 there are those time zones in some parts of asia

user507974

@yuggib his time zone (IST) is one of those

user116211

@user507974 Trump... this man 7?!!

user116211

Will Republicans choose Trump their official candidate?

user507974

11:28

@user36790 he'd just have to pass the threshold i think to be formally accepted

either that or everyone else drops out

the only republican candidate i had any interest in dropped out a while back so i lost interest there

user116211

@user507974 who?

user116211

@user507974 who is voting him btw? KKK??

user507974

@user36790 Basically a lot of people who are fed up with the main government. He is telling some of the truth but misdirecting people. The US government kinda stopped caring about its people 50 years ago and thats why were in the mess we are in now.

So he tells them this and they go like "hes telling the truth" and follow him and his colorful personality

Basically he stole the entire gusto for a libertarian revolution in my opinion so I dont like him for that.

I've been paying more attention on the Democrat side lately

user116211

@user507974: Are you eligible for vote?

user507974

Basically Trump is made out to be this scary boogeyman but the truth is he wont really be able to do most of the things people are scared he'd do.

I'm more worried about Clinton, she's about as slimy a politician as the United States has ever produced, has no principles, and the only thing she's consistent about is corporatism

user116211

11:34

@user507974 He would build those mammoth walls! He is a racist!

user507974

@user36790 Yea

@user36790 The thing is he couldn't build it

user116211

@user507974 Even Atlantic Wall was impossible. Hitler did make it.

user507974

@user36790 He won't ever even approach the needed amount of support in congress to get that approved. Our government is slow like that.

user116211

@user507974 hmm... I'm not eligible till now in Ind ;/

user116211

@user507974 I thought only Indian Courts are slow ;/

user507974

11:36

@user36790 Presidential races are frankly the most meaningless part of the political voting here in my opinion

user116211

@user507974 who basically governs US?

user507974

@user36790 Some people would disagree with me when I say this but its the people who filled up the pockets of congressman and installed previous employees into federal offices.

Much of the management of regulatory agencies tends to be filled with people who worked for the companies they now "regulate"

And worse yet there is the looming disasters like the TPP soon we wont even be able to pretend that the US is rule of law.

subject to the rule of law*

Secret

11:53

@Slereah when there are quarks, there are jets, and when there are jets, there are hadrons

Slereah

12:04

@Secret I don't care about QCD :p

Secret

$$\rimshot \rimshot (\Delta \Rimshot)$$

user116211

@Secret ooh! those red words!!

Secret

forgot how to tupe a telephoen operator

ACuriousMind

12:51

Some users...what is someone who doesn't know how conserved charges work in the Hamiltonian formulation doing reading about supergravity?

Slereah

Most people on earth

0celo7

@ACuriousMind That dude yesterday wanting to read papers on Ricci flow didn't know why Riemannian geometry should be important.

Or day before yesterday.

(And presumably didn't know any Riemannian geometry.)

@ACuriousMind Wait, how do conserved charges work in the Hamiltonian formalism

Slereah

Then again we get people asking about string theory that don't know high school calculus

0celo7

I've asked this before and got a non-answer

It's not clear at all how it works.

ACuriousMind

@0celo7 In this case, I mean that the conserved charge generates its associated symmetry just by taking the Poisson bracket with it (ignoring anomalies)

0celo7

13:03

Oh right

He doesn't know that?

yuggib

How could people talk about path integrals without knowing how a path integral could be defined... ;-P

Or better said, how could people prove QFT stuff using path integrals without knowing how path integrals could be defined

Sidarth

hey......why does annihilation take place?

@ACuriousMind

yuggib

@Sidarth annihilation of what? the known civilization?

Sidarth

hmmm....no...

for now lets just take an electron and a positron...

@yuggib do you know the answer?

Slereah

@yuggib That never stopped physicists

yuggib

13:18

@Slereah should have

Sidarth

@Slereah atomic bomb?

Slereah

@yuggib Never has :p

yuggib

@Sidarth the fact that there is annihilation is an experimental evidence

Slereah

Math history is full of gut feeling

Sidarth

@yuggib go on....

yuggib

13:20

the usual justification is that in a (special) relativistic context, matter and energy are on the same ground

and you can produce energy at the expense of mass, and vice-versa

Sidarth

but "why" does annihilation occur???

yuggib

what do you mean by why?

why does a star modify the geometry of space-time?

Sidarth

Yeah....something like that....

peeling onions

yuggib

who knows, we know it does

and we have to take that into account with a satisfactory model

but we do not know why

Sidarth

is it already the last part of the onion?

yuggib

13:24

who knows

Slereah

Shrek

yuggib

up to now, it is

Sidarth

so....we only can "describe" the process

but not answer to the "why" part?

yuggib

as for essentially everything else

Sidarth

hmm.....but we do ask why untill we hit "this is a fundamental interaction which cannot be explained"

yuggib

13:26

if you want you can give interpretations on the why, but either they are based on something falsifiable (and not yet observed) or they are not science

Slereah

you might as well ask why a particle can radiate photons

A pair disintegrating is basically a rotated radiation

Sidarth

bear with me......1)why does an apple fall?

2) cuz earth attracts it

yuggib

@Sidarth in my opinion, we mostly do ask "how can build a theory with predictive power that justify observations"

Sidarth

2)why?

3)cuz both are massive

4)so what?

yuggib

^ this is just kids play

Sidarth

13:28

5)we dont know "why" massive objects attract each other

i could ask 3 whys b4 i could hit the fundamental "why"

i.e. the last why

@yuggib I really am sincere in questioning you

yuggib

I know, but for me this way of reasoning is closer to a kids game than to scientific enquiry

(maybe it's just my opinion)

we can't know why nature "chose" its laws amongst all the possible logically coherent laws

ACuriousMind

@Sidarth Two options: Either the chain of reasons goes on infinitely, or it ends at a reason that doesn't have a reason itself - the answer to "Why?" is then "Just because". Since all human knowledge is preliminary, we can't ever determine in which of the two cases we are - everything can have a reason that we just haven't found yet.

yuggib

we can only observe them and try to describe them in the best possible way that provides further insight

Sidarth

@ACuriousMind awesome dude

@ACuriousMind so is annihilation stuck as a "fundamental" why?

something which you cannot say more about the "why" part?

yuggib

@Sidarth he just said that you could not possibly know

ACuriousMind

13:38

In this sense, we never answer the "Why?" question. We just shift the question one level deeper. The use of science is not that we find the answers to fundamental "Why?" questions. It's that we learn to describe and predict the world in powerful ways.

Sidarth

@yuggib yes.yes...

@ACuriousMind Im taking your two answers as quotes....

thanks...

Slereah

An electron positron pair annihilates because in QED there are only two processes allowed with an input of $e^+ + e^-$

$e^+ + e^- \rightarrow e^+ + e^-$ and $e^+ + e^- \rightarrow \gamma + \gamma (+ however many gammas)$

Other processes would violate conservation laws

0celo7

@yuggib huh?

ACuriousMind

13:54

@Slereah I can't find the "howevermanygammas" in the PDG ;)

It must be a particle only recently discovered

0celo7

@ACuriousMind it is the sshiggsinoino

Slereah

@ACuriousMind It's an unbound system of photons

0celo7

@ACuriousMind Can one prove the existence of the osculating circle without actually constructing an equation for it? (Definition is the circle through three points on a curve in the limit where they're the same points)

John Duffield

@0celo7 : I downvoted it because it's a "lost in maths" issue wherein there isn't anything pointing inward or outward and you've been dismissing Einstein and the evidence. Don't worry about it, I got seven downvotes for saying you can't travel round a CTC.

0celo7

@JohnDuffield But the answer has nothing to do with Einstein!

It's not a physics question!

You're downvoting a pure math question because you don't think it makes physical sense!

It's not a physics issue!

@ACuriousMind I'm confused by this paragraph. By generic, are they saying that any 3-form $\phi$ works?

@JohnDuffield If you vote to move the question to Math SE, I wouldn't hold it against you.

John Duffield

14:16

@Slereah : What guy?

0celo7

@JohnDuffield Jokela Turbine

John Duffield

@0celo7 : Hmmn, I just took a look at his answer to Where does gravity get its energy from?: "There is no Gravity, and there is no Mass. It's all just photons. What we experience as Gravity is photons with frequency <1Hz". I don't think we have much in common.

0celo7

@JohnDuffield Exactly

So you should have a debate

1

Q: Does there exist a working law of gravity in 2D?

I am constructing a two dimensional world, but ran into a problem with one of the fundamental forces, gravity. I first tried to see what would happen if I just used the normal law of gravity, $\frac{m_1m_2}{r^2}$. As it turns out, it has a problem: Consider a person standing on an edge of a "pl...

reality-check physics gravity alternate-reality 2d

@HDE226868 Does the average Worldbuilding user know that inverse square comes from the structure of 3D space?

John Duffield

@0celo7 : no thanks, I'd rather spend my time beating the woo out of you. And no, you can't exhume Einstein.

0celo7

@JohnDuffield What woo lol

user507974

14:27

hey guys, i had a question on how to do a type of derivative, mind if i ask you what i should do, kinda a little short for a full question post

0celo7

@ACuriousMind Do you have a good way for remembering $\Delta f$ in various coordinate systems?

user507974

and someone would no doubt say "google it, downvoted"

0celo7

@user507974 ask it

user507974

how the heck did you do derivatives like this $$\frac{d}{d E\beta}(\frac{1}{E\beta^2})$$

0celo7

what is $$\frac{\mathrm{d}}{\mathrm{d}E\beta}$$

user507974

14:30

basically im finding ensemble averages for another variable $\mu$

its thermodynamic conjugate is $E\beta$

David Z

@user507974 easy way is to use substitution. Make up some variable to stand for the thing being differentiated against.

so it becomes $$\frac{\mathrm{d}}{\mathrm{d}x}\frac{1}{x^2}$$

0celo7

@DavidZ That doesn't work because $E$ and $\beta$ don't have the same power

David Z

ohh, I misread it as $\frac{1}{(E\beta)^2}$

user507974

@0celo7 yea... thats been what is throwing me off

David Z

Well, that's still the easiest way to do it if there's only one "real" variable in the combination $E\beta$

user507974

14:33

technically the main problem i have $$\frac{d}{d E\beta}ln(\frac{\alpha}{E\beta^2})$$

but the same problem stands

ACuriousMind

@user507974 Use the chain rule: $\frac{\mathrm{d}}{\mathrm{d}(E\beta)} = \frac{\partial \beta}{\partial E\beta}\frac{\partial}{\partial \beta} + \frac{\partial E}{\partial E\beta}\frac{\partial}{\partial E}$.

John Duffield

@0celo7 : stuff like this:

0celo7

@JohnDuffield Lol

ACuriousMind

And $\frac{\partial \beta}{\partial E\beta} = \left(\frac{\partial E\beta}{\partial\beta}\right)^{-1}$

0celo7

@JohnDuffield cut out the parallel universe if you don't like it

the question does not depend on it

@ACuriousMind you're a wizard, Bajoran

user507974

14:36

@ACuriousMind ah so $$\frac{dE\beta}{d \beta}=E $$ so you get $1/E$

John Duffield

@0celo7 : the trouble is you can't explain why I'm wrong.

user507974

great

thanks

Kartik Watwani

any body to help on this one?

John Duffield

@Sidarth : I can answer the why part. It's easy.

@Sidarth : yes we do.

0celo7

@ACuriousMind It looks like I wrote a proof over a year ago that shows the outward normal is the one you need

Huh

Crappy memory is crappy

dmckee

14:51

@KartikWatwani TO a first approximation the area can be considered as constant across so thin a shell, or if that is not good enough you can integrate $$ R = \rho \int_{r_1}^{r_2} \frac{4}{3} \pi r^2 \,\mathrm{d}r \,.$$

The integral is, of course, just the usual $R = \rho L/A$ taken in very small pieces.

John Duffield

@0celo7 : the question doesn't depend on that parallel universe, but you accepted that whilst not understanding what clocks do. Which would have led you to appreciating that light goes slower when it's lower, and that at the event horizon, the speed of light is zero. But let's not rake that over again. Anyway, I have to go. Bye bye for now.

0celo7

@JohnDuffield Huh?

What does that have to do with anything

Danu

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Q: Deriving $E_p=\tfrac{1}{2}FL$

Using Hooke's Law, we know that the force applied is proportional to the extension of the spring. Therefore by plotting a graph of force against extension, through the area under the curve we are able to calculate the elastic potential energy stored in the spring, i.e. the work done. As there is...

forces work potential-energy spring elasticity

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