/sci/ - Science & Math

>>7322767
http://www.diracdelta.co.uk/science/source/v/o/voltage/source.html

>>7322777
that did not explain shit

>>7322767

No. Voltage is the potential energy difference between two points. Current is simply the amount of net charge moving through one point.

>>7322800
>Voltage is the potential energy difference between two points.
what does that mean

>>7322806
>what does that mean

So, when you lift a heavy weight to a higher elevation, you have to input energy, right? And you can extract energy by letting it fall.

Well, voltage is analogous. Except instead of mass and a gravitational field, you're talking about charge and an electric field. Moving a positive charge to a higher voltage uses energy, and you can extract energy by letting it flow "down." And the reverse for a negative charge.

>>7322812
What's the difference between a conductor carrying a high voltage and low current and vice versa?

Why does a transformer, having its number of turns in the primary coil be less than that of its secondary, induce a higher current but lower voltage and again, vice versa?

>>7322827
>I have a basic electrodynamics exam in less than two weeks and I have fucked off for the entire course. Please save me.

>>7322836
I'm a drop out

>>7322836
>>7322827
also, I don't think they have these in exams

i have two matrices A and B, both (20x3). Each row of the matrices represents a point in R^3, the matrix A represents the points in the Standart basis, while B represents the same points in another basis.I have to calculate the transformation matrix using matlab. The task mentioned the backslash operator somehow...
I have no fucking clue how to do this, as the matrices are not square... pls halp

Voltage is the difference of the number of electrons between two points. While current is the debit of these electrons

>>7322869
So

F = (Res*Q1*Q2) / L^2
F = (R*L*Q1*Q2) / L^2


F = R*Q1*Q2 / L


where
F: electrostatic force
Q1&Q2: amount of charge at two different points
L: length of the conducting material between the two points
R: resistace
Res: Resistivity of the conducting material (R * l)


is this correct?

>>7322836
Give him the benefit of the doubt, I think he genuinely wants to learn.

>>7322827
>What's the difference between a conductor carrying a high voltage and low current and vice versa?

You can't really "carry" a voltage, since as I said it's like a difference in height. For high voltage lines, that means the difference between the two wires is greater.

>Why does a transformer, having its number of turns in the primary coil be less than that of its secondary, induce a higher current but lower voltage and again, vice versa?

The specifics of WHY a pair of coils and an alternating current creates various voltages is more advanced E&M than can be explained in one post in a SQT, since I would have to derive it from Maxwell's laws. But at a high level, just remember that voltage * current = power, so if one goes up the other has to go down for energy to be conserved.

>>7322919
yes I 'need' to get a low level intuition

does QED cover this?

>>7322767
Voltage is the energy difference between two different points. Current is the amount of electrons flowing past a point per time period (coulomb's per second)

>>7322949
Sorry I'm drunk should be "charge flowing past a point per time" + charges count too

>>7322935
>low level
>QED
nigga you what

>>7322972
by low level I meant more fundamental

Can we have a periodic function with period <span class="math">\aleph_\alpha[/spoiler]?
How would such a function be defined, if that even makes sense?

If I have less than a 3.0, in my 3rd year of college, is there a realistic chance of having a career in engineering?

>>7322827
>What's the difference between a conductor carrying a high voltage and low current and vice versa?

Power transfer = IV

Power loss through wires during transfer = I^2 R

If you want to send the same amount of power through, but don't want wastage, you use high voltage and low current.

>Why does a transformer, having its number of turns in the primary coil be less than that of its secondary, induce a higher current but lower voltage and again, vice versa?

Conservation of Energy.

d{IV}(primary side)/dt = d{IV}(secondary side)/dt

Lower V on one side automatically increases I on the same side to ensure energy conservation.

>>7323682
i meant this.

Conservation of Energy.

<span class="math"> I_{primary} V_{primary} = I_{secondary} V_{secondary}

Lower V on one side automatically increases I on the same side to ensure energy conservation.[/spoiler]

>>7323685
Lower V on one side automatically increases I on the same side to ensure energy conservation.

Reposting from other thread:

Is the radiation put off by any of the elements unique? Like is the radiation expelled when strontium 23 decays the only way to naturally produce that particular type of radiation?

Voltage is basically like water pressure.

>>7323702
unique as in?

There are 3 types of radiation, helium atoms (yes they get shot out of atoms as radiation), electrons and photons.

there is no strontium 23, please recheck.

>>7323722
not really, more like pressure on "something" where conductivity corresponds reversely to inertia.

>>7323754
yeah, thats some alpha rad right there, yo :P

>>7323754
>there is no strontium 23, please recheck.
My bad, I just pulled a random isotope out of my ass.
>unique as in?
Frequency/amount of atoms or electrons; just some sort of indication to know what you have by measuring its decay.

>>7323754
but the alpha radiation is just the cores, ions, not atoms, right? otherwise it should not be as ionizing...

Ok /sci/, Im stupid as shit now that I have acknowledged my deep faggotry, I have to ask.

Why in the seven or eleven fucking hells a mother needs to produce more 2,3-biphosphoglicerate because the fetus joins that molecule at a worse rate?

And why(for the same reason stated above) in low pressure enviroments 2,3-biphosphoglicerate helps blood in oxigenating the tissues creating an altitude adaptation?

I must be a dumb fuck, but I really want to know these.

Simplifying square roots just seems a little like magic to me.

I understand how to solve for some:
sqrt(48...

I might've just partially answered my question. Rubber duck coding style. But I still don't know why.

sqrt(48) = sqrt(2*2*2*2*3)
the simplified version being: 4*sqrt(3)

The part I was having trouble with was "where does the 4 come from?" Why is it not 16*sqrt(3)?

My guess ended up saying that I should take the 2*2*2*2 and remove(?) half of the 2's. -> 2*2*sqrt(3)

This works on larger problems, but why do you remove them?

>>7323986
After some thought...yeah, just ignore me. I know why it works. I can "remove half of the 2's" because sqrt(4) = 2.

I'm taking calculus online and have to go through this shitty website that marks questions completely wrong even if the punctuation is off by a space. Would it be wrong to ask my professor for partial credit on the questions I got wrong?

e.g. I put [-8,9] when it should have been [-8,9) and log_6_776=5 when it should have been log_6_7776=5. For the first one the parentheses were red (meaning incorrect) when I tried to put "[ )" which is why I put "[ ]". For the second one I forgot to put that extra 7 in there.

>>7323986
sqrt(48)=sqrt(16*3)=sqrt(16)sqrt(3)=4sqrt(3)

I'm assuming sqrt(ab)=sqrt(a)sqrt(b) and all

>>7324028
Yeah I figured it out shortly after posting

sqrt(48) =
sqrt(2*2*2*2*3) =
sqrt(2*2)*sqrt(2*2)*sqrt(3) =
2*2*sqrt(3) =
4*sqrt(3)

>>7324028
assuming?

>>7324013
I would say suck it up. You made a mistake. That mistake made the answer wrong. Therefor you got the problem wrong. Deal with it.

>>7324035
assuming he knows, yeah

Does atmospheric science/climatology involve a lot of math when modeling phenomena? I thinking about changing to a physics major because my current major is not what i like, and i love both math and weather, but I'm worried that the study is less quantitative and rigorous than I'd like.

Work = force * distance
So why does holding something with your arm straight up make you tired? You aren't doing any work.

Do you burn calories just holding something up?

>>7324037
I get what you're saying, but that website is such crap. It wouldn't let me put "[ )", just "[ ]" or "( )". I don't really think that one is my fault when the website wouldn't even let me submit it as that.

>>7324044
Wouldn't have something to do with the blood not circulating so your arms get tired because there's no new blood going to them?

>>7324050
So wait...they had the answer wrong for the first one?
Expecting [x,y) rather than [x,y]? If that's the case, yeah I'd go and complain.

>>7324054
They were expecting [x,y) but wouldn't let me submit it as that (the submit button couldn't be clicked on), which is why I put [x,y] (which made the submit button clickable).

>>7324067
Yeah I was asking if that's how the answer is typically expressed. Can't say I'm well traveled in math, but I've never seen something expressed that way. If it's usually a matched brace then yeah I would complain. The site was wrong. Might want to shoot an email their way too if you can.

>>7322935
OP, read Introduction to Electrodynamics by Griffiths if you want to learn this more deeply. The first chapter gives you the mathematical tools you'll need in case you haven't taken university math yet (calculus, linear algebra etc). You can find the book very easily in PDF format on the internet and there's this series of videos by this one guy teaching each section of the book individually: https://www.youtube.com/playlist?list=PLDDEED00333C1C30E

Best of luck m8

>>7323015
Do you mean a function whose fundamental "period" is periodic? So, something like sin^2 + sin?

>>7324088
Not sure, I mean something of the form f(x + n) = f(x) where n is the period.

Maybe aleph doesn't make any sense for this, but I mean, where n is some transfinite number.

Is it a decent idea to go for a master than switching schools to a phd in physics. I have mediocre work in undergrad and if I say go far my masters, get some research in, do well in grad classes(big assumption I know) would I be in a good position if I reapply to higher level programs? Or is it best just go straight for my phd ,get in the best school I can and go with it.

Pic

>>7324101
Oh, I thought you were indexing the period with a period, getting a "jointed" period (which is of course periodic).

Ths biggest trouble with your idea is in finding an "interesting" endofunction on some suitably-large ordinal. You must also remember that addition is a bit less structured for infinite ordinals: <span class="math"> \alpha + \beta = \beta [/spoiler] when there exists a limit ordinal <span class="math"> \lambda \models \{\alpha < \lambda < \beta\} [/spoiler]. This means that such a periodic function would need to have a limit condition on the period in addition to an augmentation of our definition of a periodic function to reconcile the fact that the f(x+P)=f(x) becomes true for arbitrary P once f grows beyond the smallest limit ordinal greater than P, which makes the notion of a periodic function particularly uninteresting.

Should I study the fields of physics and chemistry before I take my general classes next semester? I have a lot of free time until my semester starts and I want to finish my medical school pre-reqs with a good GPA so I can crush the MCAT

>>7324181

in addition to this question, would taking general biology, general physics and general chemistry be too much science for one semester at uni?

>>7324181
Like watch videos on Khan Academy? If so, then sure. If you have the free time then spend it prepping for your next semester classes. You could even buy a study book for the MCAT and look that over if you want. Each entrance exam expects different levels of knowledge that's usually explained in the study book. For example, you may think you only need a little background in microbiology you may actually need to know a whole lot. I'm not prepping for the MCAT so idk really on that.

>>7324190
Depends on what kind of student you are. If you're prepping during the summer then you may be able to handle it all. If this is your first time taking any of those courses, maybe just take two and balance it out with an easy class. You will need to take all those classes eventually but it's important to keep your sanity and your GPA high.

>>7322846
They can be seen as square matrices by thinking of the other points as zeros.

2 3 = 2 3
0 0

>>7324217

Thanks m8.

That's a good idea on taking two at first and seeing how I can handle it. I took Anatomy, Statistics and Intro Chem last semester and did well (3.7gpa), but a General Chem class is probably a lot harder than Intro and I struggled a little bit. Will probably just take Biology and Chemistry next semester (since intro is still fresh in my head.)

Khan Academy is a good idea. I can start watching some basic videos. What's generally harder? Chemistry or Physics? I'm not really concerned with Biology. I do very well in life-science classes since I am a good note-taker. Practical applications are a bit harder for me.

>>7324044
>Work = force * distance
>So why does holding something with your arm straight up make you tired? You aren't doing any work.

You're not doing any work on the thing you're holding up, true. But there's a lot of internal work going on in your muscles in order to hold their position. There's no inherent reason why that may be so (a table isn't donning any work holding the same thing), is just how our bodies work. Basically, chemical potential energy is turning into heat.

>>7322846
To linearly transform <span class="math">f(A_{m,n})=B_{m,n}[/spoiler] you either have to right-multiply it with <span class="math">R_{n,n}[/spoiler] or left-multiply it with <span class="math">L_{m,m}[/spoiler]. Since we're dealing with 3-vectors, it only makes sense to have a 3x3 transformation matrix, i.e. right-multiply the row vectors.
<span class="math">A\begin{bmatrix}
xtox & xtoy & xtoz \\
ytox & ytoy & ytoz \\
ztox & ztoy & ztoz
\end{bmatrix}=B[/spoiler]

I don't see how backslashes are relevant, unless they're a way for matlab to generate the transformation matrix given A and B.

>>7324283
>Unknown control sequence '\\'
nigger ass bitch cum gargling niggerfaggot
\\ is valid mathjs

must math be a single line or what?

>>7324035
you can only assume that if you are dealing with non-negatives.

>>7324291
> must math be a single line or what?

yeah. 4chan disabled it to protect from abuse or something.

>>7324228
I took biology and chem at the same time and it worked out well because there's quite a bit of chemistry in upper level biology courses and of course there's biology in biochemistry. I'm more of a biology person but I understand chemistry better than physics. If practical applications are a bit harder for you (they are for me) then physics may be tougher. If you do your prep and ask the professor questions when you have them you should be fine.

>>7323770
The frequency, or rate of decay, has to be statistically determined, due to decays being random. Only when taking a large sample, and waiting long enough, do you see a unique half life.

Alpha and gamma decays, helium nuclei and photon respectively, are single particle decay. ie Parent atom => alpha/gamma particle + daughter atom. In this case, kinematics (conservation of energy and momentum) give such decay particles a definite E and p, and are therefore unique to the particular decay.

Beta decay on the other hand, the decay that spits out an electron and a invisible neutrino, is a 2 particle decay, so the energy and momentum of the electron is a distribution. Also somewhat random, requires statistics to determine the decay energy.

>>7324731
>Beta decay on the other hand, the decay that spits out an electron and a invisible neutrino, is a 2 particle decay,

Sorry i meant 3 (or more) particle decay.

Parent atom => electron + anti-neutrino + daughter atom

>>7324736
>>7324731
Alright, thanks a lot for that.

How do I into mathematics?

What's the best material for a lab coat?

i have no idea how they did that

>>7322767
This must be a REALLY dumb question but uhm ...

How the fuck do I deal with an inductor when searching for a thevenin equivalent resistance?

>>7324163
I see.

On the other end of the scale, how would a function with an infinitesimal period work?

Force is the derivative of momentum with respect to time

allahu akbar

Hey /sci/ does any one of you know why the art of electronics 3rd edition isn't available for download on any torrent site yet? I mean it's a pretty popular book, so I've expected someone to have taken the time to scan it. Some anon claimed on /diy/ that it will be released as an ebook in June, but when I searched for this, I didn't find any source.

Where can I torrent "The Mechanical Universe" series by caltech?

Is angular momentum measured in mass * velocity * distance(linear momentum times distance) because it is the sum/integral of all the linear momenta of all the points of the object?

>>7325419
have you tried looking on pirate bay?
https://thepiratebay.vg/torrent/6103269/
https://thepiratebay.vg/torrent/6103283/
or you can download this one:
http://kat.cr/the-mechanical-universe-and-beyond-t10372366.html
the bigger size implies better quality.

>>7325078
>How the fuck do I deal with an inductor when searching for a thevenin equivalent resistance?

The same way. You just use the impedence of an inductor and solve the same way you would with just resistors. You'll just get an answer that is a complex number and a function of frequency. (If it's a DC circuit, then an inductor = a wire)

>>7325437
yeah, last time I was looking piratebay was down
also, thanks

>>7325434
In vectorial mechanics:
It's because the strong form of law of action and reaction leads to conservation of something we named "rotational momentum"

In variational mechanics:
It's because Noether's theorem applied to the isotropy of space leads to conservation of the same quantity, angular momentum.

>>7324044
>Do you burn calories just holding something up?

Yup, and you are doing work - your arm is twitching up and down, and a stretched arm is a lever which intensifies this. If you take the same weight and hold it in arms stretched downards (but still holding it in your hand) so you don't have a long lever, you get tired slower.

>>7324291

I'm pretty sure "nigger ass bitch cum gargling niggerfaggot \\" is invalid mathjs

>>7324966

Depends on what you're doing. If you e.g. spill Nitric Acid on a cotton coat, it turns into a coat made from gunpowder. Good times.

>>7325079
Hmm, I'm not enturely sure. Seems like such a function could be constructed.

Guys, I have a choice of getting an Engineering degree at a CSU or at a middle tier to lower tier university, or get a Business Degree (Finance/Accounting/Economics) at UCLA and other higher tier universities. What would you choose?

>>7325484

Please tell me you're trolling.

>>7325620
stay pleb stupid nigger

>>7325644
you're expending energy even if you're not doing "useful work" on the item itself. next you're going to tell me that you're not doing any work by walking on a level surface because you circumvent friction by LIFTING and MOVING your feet to circumvent the friction of the surface...

Where would I use Calculus III and Differential Equations in the real world?

>>7325769
>Differential Equations

Whenever you try and model something. I used them a few months ago to decide what would happen if I got a wood burning fire.

>>7325769
> calc 3
modelling fluids
> differential equations
modelling anything in physics

>>7322767
is it possible to make an ion drive that only uses electricity to shoot electrons to make thrust? (not ion drives they use ionised gaz, im talking pure electrons)

>>7325825
i would think so, like a particle accelerator

>>7325845
yeah, like a CRT but you let the electron go

Hey /sci/entist, I want to hear your career - stories and what obstacles you had to overcome while going that path.

Also more interesting/strange/curved paths are welcome, like dropping out of college, learning a profession and then catching up with it after a couple of years, etc.

>>7325494
Nitrocellulose != gunpowder

If matter is defined as having volume ( three dimensions ), would a square kilogram as seen in Newton's Law of Universal Gravitation exist in the sixth dimension, as well as gravity?
I'm not smart btw

>>7325045
If you multiply the original statement by an arbitrary amount of 2's on either side, as long as they are offset by a multiple, you would get the 2nd equation.
After that, it looks like they equated the exponents of the 2, but I can't see why that would would make sense, unless k=m.
This is actually bothering me.
Anon, are we both retarded? Or is this problem?

If I don't really care about what I'm visualizing in a graph, but I kind of enjoy working out Math Problems and be able to solve them by learning patterns and such. What does this make me?

>>7326824
A mathematician.

That's how math works above calculus.

>>7326852

Oh god, I don't want to be poor.

Why does a Mathematician have to do Physics?

>>7326905
>poor
>300k starting
>any job you want

Could anybody help with this? Also to whoever helped me ~15 hours ago is a lifesaver, thanks a lot for that.

>>7326958
woops, meant to post this.

I've got a question.

I'm supposed to prove something about two sequences. I've got two series a_i and b_i, both decreasing, and both sum to 1. Basically, I need to show that, if a_n>=b_n for all n, then sum a_i >= sum b_i.

I know I need to use induction on each a_n, letting n=1, then letting n=k+1, and proving it still holds, but I seem to get stuck at the induction step. How do I prove it for k+1?

>>7322767
>Had female friend in High School who could do that
>Decide to talk to her again because almost got pussy back then (her pussy)
>She is with some nigger now

How come transfer requirements are much harder for engineers than for Math?

Does an applied Mathematics major have to learn proofs?

>>7322767
I dunno if I can add anything to what's been said but I'll try. A voltage corresponds to the electric potential energy difference between two points. In a battery, what you're doing is creating a potential difference using a chemical reaction. That potential difference is what moves the charge, because it tends towards it lower energy state, in the same way a ball does when it falls. the electric field is an abstraction of this in which every point in space is assigned a potential. in a circuit attached to a battery, electrons are driven at a relatively slow rate (in the order of cm.s-1 i think) around the conducting loop to the lower potential terminal. this means that every point experiences a flux of current equal to the voltage divided by the resistance (or the resistivity multiplied by the length). the reason it's hard to say this corresponds to the potential energy of the electrons is because once you get into semiconductor physics the situation gets a lot more complicated, but for a lot of purposes this racetrack intuition is pretty good.

>>7326583

Of course it isn't but who gives a fuck. "gunpowder" is faster than "nitrocellulose, which has replaced gunpowder as the primary accelerant in modern firearms"

Is it possible for a charged particle to have zero mass and vice versa?

p.s. neutrons technically still contain charges even though they cancel out

So what I did with this problem was that I set x and y equal to 0 to get two other points. I then got two vectors out of them for a total of three vectors. Afterwards, I did the determinant and got an equation out of it. However, I got the equation wrong. What am I doing wrong?

Has anyone proven yet why matter cannot have a velocity higher than that of light?

>>7322767
For a computer engineering degree, should I take the Software or Hardware track? I'm equally interested and experienced in both.

Is it possible to suck at math and want to major in applied math?

>>7327145
What do you mean by 'suck at math'?
Are you straight out of high school?

>>7326823
I have no idea dude

>>7327148

In college taking calculus three in the summer. 5 hours of studying everyday and I still don't understand.

>>7327546
>5 hours of studying everyday

Try tripling that amount

>>7326062
No one here is a scientist, don't fool yourself

>SQT

Is khanacadamy the best place to do refreshers for math? It's been 11 years since I had any kind of schooling and I have to take an entrance exam to get into school. Math is the only thing I'm worried about.

>>7327580
>>sqt
suomi qt

Anyone here knows the energy required to separate carbon and oxygen in CO2? I know it can be done, but I can't find any technical data ANYWHERE I look and I need it for a paper. Haelp?

Keep in mind I'm not talking about the CO2 > CO + O process, I mean complete separation of the two elements with no carbon oxyde left

>>7325045
>>7326823
Every number has a unique factorization into primes. The idea of the proof was to show that the left side of the equation contains an odd power of 2, while the right side an even (this is the part you've circled). Since they have different prime factorization, they are different numbers.

>>7327614
add the enthalpy from the CO + O = CO2 and C + O = CO

>>7327025
Yes.

In fact at my school, our degree is called "applied mathematics" for bureaucratic reasons, but there are many abstract proof courses involved.

>>7322836
>2 weeks

i haven't learned 2 weeks combined per semester during my EE course
(i attended all the classes and shit tho)

Hello /sci/ i'm mathematically inept and need your help.

I'm trying to figure out how many times there is an "increase" when the starting number is 1020 and the final number is 90900

Each increased amount is an amount (240 currently) + the next amount+20, so the next step is 260 afterwards 280, 300, 320 etc.

I hope I make enough sense for anyone to figure out what i'm after.

Manually counting this would drive me mental.

>>7327648

1020+x*(220+20*x) = 90900

find x

What does happen to a particle moving with constant speed when it hits a wall also moving with constant speed, not necessarily equal to the particle's speed? Does its kinetic energy become 0.5m(v_particle + v_wall)? Assuming there's no loss of kinetic energy during the process

>>7325769
Calc 3 is Multivariable/vector?
Diff equations are good for pretty much anything. I use them to find the right amount of sugar in my coffe (not even kidding)

>>7327661
that seems right

>>7327648
if you're just interested in the answer it's approximately 61.673

http://www.wolframalpha.com/input/?i=1020%2Bx*%28220%2B20*x%29+%3D+90900

>>7328076
>putting sugar in coffee

you should find the equation of proper coffee extraction so you shouldn't put sugar into your undrinkable shitty ass "coffee"

>>7328196
>61.673
typo, meant 61.763

>>7328197
>stop liking what i don't like: the movie

>>7327648
>>7328196
wait i don't think >>7327661 is right. i'll make a computer program to try to find out the answer.

>>7327648
here you go bruh
>number is 90900 after 84 steps

>>7327621
Thank you, I read up a little bit and wouldn't it actually suffice to take the heat of formation for CO2? If I understand correctly, if I apply that energy to CO2 I can divide it right?

>>7328230
for a more "mathematical" method we can use the sum of an arithmetic series.

1020 + n * (240 + (220 + 20 * n)) / 2 = 90900

the positive solution for this equation is indeed 84:
http://www.wolframalpha.com/input/?i=1020+%2B+n+*+%28240+%2B+%28220+%2B+20+*+n%29%29+%2F+2+%3D+90900

>>7328076
> I use them to find the right amount of sugar in my coffe
no you don't

>>7327996
Solve the problem in the rest frame of the wall and then go back to the original frame to help you see.

>>7328304
If the wall is at rest, then the velocity of the particle with respect to it should be \frac{1}{2}m(v^2 + {\dot{x}}^2), where v is the wall's speed and \dot{x} os the particle's speed. I summed the velocities because they have opposite directions. If there's no loss of kinetic energy, then the particle would bounce back with the same velocity v^2 + {\dot{x}}^2.

Is that correct?

>>7328385
Welp, seems like my latex didn't work out well

What's the difference between Pure Mathematics and Applied Mathematics?

>>7328394
It's pretty obvious, isn't it? Pure mathematics does not need any real world application, whilst Applied mathematics does. Pure maths can become applied if anyone finds an application for it.

>>7328400

Do both deal with Proofs?

>>7328385
Not quite, you don't sum the squares, but square the sum. Anyway, you don't need to take energy into account if you take as given that the velocity of the particle is reversed.

>LAB FRAME
Particle velocity=v
Wall velocity=-u

>WALL FRAME
Particle velocity=v+u
Wall velocity=0

After collision in the wall frame, the particle has velocity -(v+u). Therefore, in the lab frame it has velocity -(v+u)-u=-v-2u

>>7328394
One can feed a family of four, the other cannot.

>>7328406
Obviously.

>>7322767
Why don't we have futurology threads like the SpaceElevator threads on /pol/? Basically a thread that posts interesting / cool research and projects.

>be me
>try to do my community Math classes in California
>do great in the computation
>do linear algebra
>they have proofs
>have to do proofs
>completely don't get it

If I wanted to get into Engineering or Applied Mathematics, do I have to get good at proofs?

>>7328442
It doesn't matter what you want to get into, but you'll have to pass the courses along the way and if they require proofs, you'll need to learn them at whatever level they're being taught and required at exams.

Engineers don't usually do proofs in their jobs, I'm not sure about applied mathematicians, though.

>>7328442
Lol, if you're in a serious applied math program you're going to be two or more semesters of analysis anyway, so prepare your angus

>>7328407
Alright, so the actual problem I'm trying to solve is the one of a particle bouncing between two walls that are closing in towards the middle of an one-dimensional box. The part I'm struggling to understand is if the particle keeps moving with constant speed at all times or if it gains a little speed when it hits one of the walls, going faster after each hit.

Why am I better at math when I listen to Greek black metal? I was stuck on a problem, but I put on some old Rotting Christ and immediately powered through the rest of the set.

>>7328464
All those greek letters man

>>7328463
Yes, it gains KE after each collision.

Before:
<span class="math">K=\frac{1}{2}mv^2[/spoiler]

After:
<span class="math">K=\frac{1}{2}m(v+2u)^2=\frac{1}{2}m(v^2+2uv+u^2)[/spoiler]

Thus, change in kinetic energy per hit is:
<span class="math">\delta K=\frac{1}{2}m(2uv+u^2)[/spoiler]

This is actually how Fermi acceleration works, which is simplified if you assume that the particle is moving relativistically.

>>7328474
That's what I don't get, though. If the collision is elastic, then shouldn't the total kinetic energy be conserved? The wall will keep moving with speed v, but the particle will have gained some speed, thus it'll have gained kinetic energy.

>>7328464
Are you greek?

>>7328463
>>7328474

Adding to this, if the box has width L, then there is a collision every:
<span class="math">\delta t=\frac{L}{v}[/spoiler]

and thus:

<span class="math">\frac{\delta K}{\delta t} \approx \frac{dK}{dt}=\frac{mv(2uv+u^2)}{2L}[/spoiler]

and putting v's in terms of K's (or vice versa) you can solve the energy as a function of time.

Just saw this >>7328486 . The mass of the wall is huge, it loses some kinetic energy in the collision, but since it's mass is so great it barely needs to lose any speed. If still unsure, solve a 2 body collision for two particles of masses m_1 and m_2 and see what happens as m_2 goes to infinity.

>>7328491
No

>>7328486
GREAT QUESTION

THE KEY IS THAT THE MASS OF THE WALL IS INFINETLY BIGGER(>>) THAN THE MASS OF THE PARTICLE

So actually the wall DOES slow down with every hit ( the kinetic energy is conserved) but this slowing down is infinetly close to 0 , so we consider it to be 0

In other words the kinetic energy that the wall loses ( which is equal to the kinetic energy the particle gains) is infinetly small compared to the kinetic energy the wall had because M>>m

So we consider that loss is 0 so to make
he problem easier ( v stays the same )

I can prove it if you are not satisfied

>>7328523
>>7328486

Isn't this system just giving kinetic energy to the particle out of "thin air"? Each time the particle hits one of the closing-in walls, it'll gain some KE so it'll keep going faster until the walls finally close onto it.

>>7328524
Isn't this system just giving kinetic energy to the particle out of "thin air"

No, the walls are giving some of their KE to the particle, such that total KE is conserved. The point is, the walls are so massive that they effectively do not slow down, despite losing energy.

As a different example: think about jumping. Momentum has to be conserved, therefore when you jump up with momentum mv, the earth has to go in the opposite direction with momentum MV=-mv. Thus, the momentum of the earth is the same as yours, but its speed V=(m/M)v. Since your mass is much less than the Earth (unlike ur mum) V<<v. i.e. effectively zero.

>>7328534
Ok, your answer satisfies me. Thanks so much for the time, m8!

>>7328540
no problem m80

>>7328524

Yes the KE of the system is getting Bigger and Bigger with every hit ( which is impossible) because to make the problem simple we have accepted that the tiny amount (infinetly close to 0) that the wall slows down will be considered 0 so v remains the same

The wall is giving kinetic energy FROM ITS OWN KINETIC ENERGY but what is giving is so small compared to what it has

Imagine a ship hitting a mosquito (elasticly )

The mosquito will go faster and the ship will practicly slow down BUT NOT FUCKING REALY.

The wall is the Ship and the particle is the mosquito

The wall/ship has a lower v with every hit which is ALMOST EQUAL to its previews v

to make the problem easier we say its EQUAL
so v remains the same and YES IT LOOKS LIKE KE IS GETTING MORE AND MORE.( which is actualy not true)

>>7328551
Just one more thing. I can understand how the particle's speed would be v+u in the wall's frame, but I don't see why'd it be that in the lab's frame. My calculations show that it should be just v after the collision, but in the opposite direction.

>>7328573
Think carefully about your signs m8, when you switch between frames do you move to the right or the left. Night.

>>7327124
its not really possible for any particle to have zero mass. you can have zero rest mass like a photon, but they still have energy from their movement. if they have zero energy then the cease to exist.

yes, it is possible for a massive particles to have no charge

Is there any realistic size limit to how big oceanic creatures can be? I mean, could there theoretically be an animal in the ocean that's like twice as big as a blue whale or some such? And I don't really mean in terms of something like a large jellyfish, but you know, say a big ass creature.

Or are blue whales really the limit?

>>7328603

Maybe deep deep down in the ocean that we still are unable to go down to.

>>7328601
Thoughts have zero energy.

>>7322836
no that is wrong

>>7328256
With an electrolytic process yeah

Can someone give me an example of a proof for intro to Applied Mathematics? Say someone who transfers from a CC in California to a university in California.

How hard is it to get research experience as an undergrad? In transferring to a research university in the fall and would like to get some experience working in a biology lab.

>>7328603
A very thinly veiled 'is Cthulhu real?' question
>

>>7327580
Probably.

They of course have videos with examples/explanations but also have numerous problems you can do too.

Calculate the % regenerative efficiency of a plate heat exchanger installation in which:

Cold milk is preheated in the regenerative section from 7 degrees Celsius to 70 degrees Celsius

Pasteurised hot milk is cooled in regenerative section from 76 degrees Celsius to 10 degrees Celsius

I got 87% but I don't think it is right. Anyway know how to do it

>>7328603
>>7328975
this is scary to think of

What kind of study environment do you all prefer? I'm seriously contemplating getting one of these to study in, because i just can't avoid distractions and feeling bored in large, open spaces. Any advice?

>>7328601
if they have 0 energy it means they are still
( thermal death, 0 kelvin )

>>7329119
If they have a "quiete study zone" in your library with those desks I highly recommend trying them out. I would go to one after class during my two hour break and it made me self conscious when I would browse my phone so I got a good amount of studying done. The desk is important but so is the environment. If you have one of those desks and it's not completely quite then it may not work as well.

>>7328601
>its not really possible for any particle to have zero mass
so, all charged particles have to have mass--no mass, no charge?
>yes, it is possible for a massive particles to have no charge
what elementary particle has no charge?

What are closed, surface integrals for? why are they called integrals if they're just multiplying something by something multiplied by pi?

Also, does multiplying something = integrating that something such that that something is a constant with respect to whatever it's being multiplied with?

What is a system of coordinates?

I know it's a pair, but what is it supposed to be for example in the case of the cartesian system of coordinates on <span class="math">\mathbb{R}^n[/spoiler] or the other common ones for the case of n=2,3?

This may be a long shot, but I am in need of reading on torsors over schemes, and Google is not helping much. Does anyone understand these at all?

>>7322767
really not
you can consider the voltage as the strenght of the flows of electrons..
try to read up about electrochemistry and daniel cell
.

>>7327646
>wasting your life to get a piece of paper

What gives when it's impossible to invert conjugated momenta equation in order to make the generalized velocities functions of (q,p,t)?

Anyone mind giving me some help on this statics problem? I've done 1-4, but not sure where to begin on 5 and 6.

TDE = 40
TDC = 34.64
TCA = 24.70
TCB = 27.94

Does sleep-learning work at all?

>>7330126

I calculated those numbers wrong (used 20 instead of 100 like the pic says) Real forces....

TDE = 200
TDC = 173.21
TCA = 123.58
TCB = 139.24

>>7325045
As far as I understand French, the point is to show there are no such natural numbers x and z that z^2=2x^2. They then assume there are two numbers k and m such that 2^shit *k^2=2^different shit *m^2, and then achieve the desired contradiction with 2*crap being both odd and even at the same time. But then they claim there are no such natural numbers x and y such that 2x^2=z^2.

My conclusion: they fucked up their writing pretty badly. Not only did they mess up with the letters k and m, they also pulled some random y out of their ass.

Riverdance the bad vibes away https://www.youtube.com/watch?v=2mDSLDJPPdw

>>7330126
the answer to 5 is 75 kg
you draw all the forces and you assume that the biggest ( in our case the one from D to E and its reaction ) is 1500N
then its just geometry

>>7330183
To be honest, I, too, am puzzled as hell now. It can't be like I just wrote, otherwise they'd just use 2 instead of those exponents there. Why, why, why?

What are the requirements to learn goldstein. I'm guessing an intro to physics class, 1st year calc, multivariate calc(?) and diff equations (?)

>>7330075
Trying to solve this problem, but I can't get the generalized velocities as functions of q and p. It's actually impossible since I can only one of the equations have \dot{y} and \dot{z} while the other two only have \dot{x}.

Is the fact that the potential doesn't depend on z a hint to solve the problem? Should I use an alternate method to find the Hamiltonian that skips this part?

>>7330126
the answer to 6 is 45 degrees
to solve you draw the mg force at DF and its reaction. So now you have 2 forces drawn on D : mg and mg'=-mg

Now you analyze mg' in two forces one on DE and one on CD

you assume CD=1000N and you know that mg'=1000N

So easily φ=45 degrees

If you do a pythagorium DE=10^3(root)2 < 1500 so we are fine

may I ask for what class are you solving these?

>>7330242
they're asking for the minimum angle that would support a 100 kg lamp. 45 degrees isn't the minimum angle.

>>7330192

Thanks for the clarification, I actually got the same answer right before you posted. Still working on 6, since the other anon here >>7330276 disagrees.

>>7330126
OP here, does this sound right for #6?

1500cos*theta - 1000 = 100
theta = 42.8

That is similar to how I solved for 5.

>>7330337
not sure what you intended with
>1500cos*theta - 1000 = 100

but my solution is that DE needs to support 1000 N in the y direction, and 1000 is 2/3 of 1500, so you're looking for sin(x degrees) = 2/3, 0 < x < 90, which makes the answer approx. 41.8 degrees

>>7330209
Bump

>>7330372

Thanks, I like that much better than mine.

>>7330194
>>7330183
>>7326823
that was the informations given

>>7330372
>>7330242 im this anon

DEy is 1000, I agree but how do you get φ=42?

If DEy=1000 N then for D to be balanced DEx=DC
to find the minimum angle I took DC=1000 so I get φ=45 degrees

where am I wrong?

>>7330517
cont
if φ<45 then DEx>1000 so DC>1000 not acceptable

>>7330490
I still don't understand why they use k and m or α and β. There is already the assumption that 2x^2=z^2 with the numbers being non-zero. Why not just show that this implies 2^(1/2) is rational? It'd be so much less confusing.

>>7330372
cont
in your solution DEx is aprox 1118 so DC=1118 aprox, not acceptable

>>7330546
Or does there actually exist a book that doesn't include the set of rationals in the same chapter with the naturals?

>>7330546
The way they do it using prime factorization is much more natural. The solution just didn't give much of an explanation as to what they were doing.

voltage is the electric potential, basically the integral of the electric field. (assuming conservative)

the current is not an energy. the current is more like an electron flux. its a measurement of how much charge is going through a cross section of the wire per second

>>7330517
>>7330548
ah i think we're both wrong. my 41.8 degrees answer assumed that DC could handle it. but as for your solution, 1500cos(45 deg) is approx. 1061 N which is also over the limit of 1000 N.

my revised solution: first we find a lower bound for the angle at ~41.8 degrees because of >>7330372. but we also need to make sure that DEx is at most 1000 N (DEx=DC, DC <= 1000 N), so we have 1500cos(x degrees) = 1000, 0 < x <= 90, which leads to the answer arccos(45 degrees) = ~48.2 degrees.

>>7330668
>arccos(45 degrees) = ~48.2 degrees
meant arccos(2/3) = ~48.2 degrees

A bit late but hopefully someone will answer. How hard REALLY are Calc 2 and 3? And what comes after Calc 3? Linear Algebra, DiffEq? Where does discrete play into all of this? Thanks in advance

What is this light?

https://www.youtube.com/watch?v=MvacG_nhD34

>>7330680
It's hard if you don't have a study habit and if you have low mathematical maturity. Also depends on what is Calc 2 and 3. It usually varies, depending on the school.

Why are you making this question?

>>7330680

easy as fuck

>>7330682
the moon i guess

>>7322767
If the set containing the infinite number combinations NOT containing the complete works of Shakespeare is a larger infinity than the set containing the infinite number combinations that DO contain the contain the complete works of shakespear. Doesn't that mean a monkey will likely NOT type the complete works of Shakespeare even given infinite time. considering you can only type one infinite set in an infinite amount of time.

>>7330718
edit: I meant letter combinations*

>>7326993
>racism
This is the very reason you will never get a long lasting relationship and end up a cuckold like you did to your girlfriend. Nice to know that your obsolete genes wont survive past this generation.

>>7330718
The infinite set contains all other sets.

>>7330757
I can construct many infinite sets that do not contain all other sets.

The universal set contains all other sets.

>>7330691
Calc 2 being integral calc and calc 3 being multivariable. And I only ask because I don't want to clutter up a different thread and because I'm interested in taking them.

Why isn't the force 0 when an object isn't moving(static force)? What's the acceleration if not 0?

>>7331039
Who said it wasn't?

>>7331040
well, I'm definitely exerting a force on my chaireven though I'm not moving

>>7331072
Net force man, not force.

>>7331090
elaborate

>>7331072
the chair counteracts your force so the net force is 0.

>Newton's Third law: When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body.

>>7331129
how much force does a 1kg object laying on te ground exert on the ground? 1kg * 0/s^2?

>>7331145
About 10 newtons

>>7331149
what

>>7331152
>>7331149
ohh I feel so stupid right

>>7331145
1 kg * 9.8 m/s/s= 9.8 N
pay little attention to the units of 9.8 m/s/s.
Gravitational field strength has the same units as acceleration.

>>7331145
force is mass times acceleration
F = ma

the gravitational acceleration at ground level is approx. 9.8 m/s^2 and the mass is 1 kg so the force the object exerts on the ground is approx. 9.8 kgm/s^2 also known as 9.8 N (9.8 newton).

Why do we sweat if it's 98° F outside, when our internal temperature is the same?

>>7322767
I dont know shit about electricity but a EE friend told me to look at voltage like the height of a waterfall (higher voltage = higher potential and faster water speed), and the current like the amount of water flowing through the river per time

>>7331341
>Why do we sweat if it's 98° F outside, when our internal temperature is the same?

Because your body is constantly producing heat - roughly 100 watts. In order to maintain a constant temperature, something has to be cooling it at the same time. If your surroundings are cool enough, the excess heat can simply dissipate into them. But if they are near or above body temperature (or you are too well insulated, like wearing a winter coat), then passive cooling isn't enough.

>>7330727
This guy right here isn't white.

How to solve system of 3 equations with 3 unknown variables with Cholesky decomposition if the starting matrix made from those equations isn't symmetrical? I've looked up some stuff on the internet but that's just too much work.

>>7322767
What's worth knowing about comets?

>>7322767
What's the difference between "hyperbolic","elliptical", "parabolic" and "highly eccentric"?

I know that they're all to do with maths shape things, but do they mean anything special in physics?

>>7326905
>>7326934

>>7324044
Its because our muscles work with twitches. There are animal muscles that can hold position with much lesser work expenditure. The muscles in our arms don't do this however and operate via short bursts of higher energy

http://physics.stackexchange.com/questions/1984/why-does-holding-something-up-cost-energy-while-no-work-is-being-done

>>7324044
"work" is expended energy, not just force * distance. force * distance is just the amount of energy expended when moving an object. for example heating something up or cooling something down is work too. it's absolutely disgusting the way "work = force * distance" is getting taught in schools.

https://ccrma.stanford.edu/~jos/pasp05/Work_Force_times.html

http://physics.stackexchange.com/a/134397

>>7329378
Closed surface integrals are useful for determining how much stuff is going into our coming out of a given volume. For example, we can prove charge conservation using Maxwell's equations and surface integrals, by manipulating one of them you can show that the change in charge in a volume over time is the same as the current going in/out of the volume, thus proving that to add charge you must bring it from somewhere else.

Surface integrals aren't really anything to do with Pi, you've probably just dealt with circular surfaces and such like where it will obviously pop up.

I don't really get your last question.

>>7331641
>heating something up or cooling something down is work
uwotm8 uavinagigglem8

>>7331825

do you ever get used to formatting documents with latex?

>>7322767
Is pressure the force of particles bouncing/smashing into something?

I always imagined planes fly because particles smash the underside of the wing, and because it's at such an angle, it pushes the plane up.

If I had a tube between a low pressure and a high pressure, and since particles are bouncing around, the high pressure particles will start to spill into the low pressure zone because there's less resistance that way.(less particles to bounce into)

Same with flow of electrons.

Am I right, or is this simplification completely wrong?

>>7331924
Yes. It becomes e z p z after the first ~5.

Why are black holes allowed to exist? Won't everything in the universe eventually be sucked into one?

>>7332509
https://en.wikipedia.org/wiki/Friedmann_equations#Density_parameter

>>7332509
Basically the universe will collapse in on itself or everything will be completely separated, turned to shreds, and cold. Depending on the universe's mass/energy density.

>>7332358
I'm a certified dingus, so take this with a grain of salt .

The first part is mostly right. Pressure is how tightly packed the atoms are/collisions per second. Heat makes atoms go faster, so there's more collisions per second, and more pressure.

Can a dwarf have gigantism?

>>7332640
Can you drown parasites?

>>7332638
Possibly. Gigantism is caused by the pituitary gland secreting too much growth hormone. Dwarfism can be caused by not enough growth hormone secreted but also could be genetic. If one of the X's in a female is defective or you inherite a mutated gene that could cause dwarfism.

Not sure what they would look like though. Huge head with disproportionately small arms?

>>7322767
Is voltage same as pressure?

>>7333026
Not quite. Its more like elevation. A positive charge at higher voltage wants to "roll downhill" to a lower voltage

>>7333047
that is exactly what pressure is analogous to

does an object traveling in a circular path at 10 meters have the same kinetic energy as a object traveling in a straight line for the same distance?

What are some tips to develop better study habits. I feel like that I spend way to much time ducking around and get pretty distracted when I try to sit down and study.

>>7333065
realize that you have 24 hours a day. you sleep for 8, do whatever you want for 8 and work for 8. if you're unemployed that's your study time. if you're employed then you got less time, but there's still time to do it on a daily basis.
play some music to get you going.

>>7333065
Alpha bineural beats have become a staple for my study sessions. It keeps me focused on my notes and drowns out any background noise. I only let myself turn it off when I'm on break so I'm aware I'm not studying. It takes some getting used to so I'd recommend starting out with the volume low and just read a book or something. Then as you get more accustomed to it integrate it into your study sessions.


This is the track I use: https://youtu.be/oTuEvnfgQcY

>>7333065
depends on your personality I guess
what stuff are you interested in/ what stimuli do you respond well to?

>>7331921
You proved nothing, the heating up of the gas changed it's volume. Even that isn't work, it's only work if that changing volume of gas moves a solid object. If you expand gas into a vacuum no work is done. You don't fully understand the concept of work. It is what it says on the tin; literally doing work. That is what it is defined as, the energy required to lift or push something. Heat energy is just heat energy it is not work energy because it isn't doing any work.

>>7333065
Do a tiny amount of study first and then slowly increase each day. Jumping in front of the book for 3 hours on day one will cause burnout and disillusion. Also think carefully about why you're studying the subject, If you get distracted then it sounds like you aren't interested in the subject.

I'm trying to remove a thick layer of paper that's used on the binding of a book. It sits on a thin layer of strong adhesive. However, I can't melt the glue because the paper layer is shielding the glue from the iron that I'm using to debind.

Is there any way to dissolve or weaken the paper layer that doesn't compromise the pages of the book, or get me killed?

>>7333115
keep thinking different "types" of energy don't refer to the same thing just because you use different letters to denote them. if you said "mechanical work" i'd agree but "work" can be anything that you do that takes energy.

>>7333115
and TRANSFERRING heat energy is doing work because you are MOVING the heat energy

Is it worthwhile to become a science or maths teacher for a few years to pay off your university debts and save for your first home? (Australian here by the way))

I would have an extra year of study to do on top of my degree already with an extra $10,000 added to my debt.

However mathematics teachers are currently in demand so I think the prospect of getting a job is high and worth it.

>>7333115
Well thats not quite right, if an expanding gas moved a piston then the gas would be doing work on the piston, in particular it's "mechanical work". However heating up a gas would mean that work is done on the gas. As this anon >>7333480 says, work is done when energy moves.

>>7328442
yes, but many people have problems at first with proofs.

Only after Uni courses I understood (relative simple) proofs, but it's enough for me to get by (compsc).

Math without proofs would be pointless

>>7333090
wtf is this shit?

Does it actually work?

>>7333589
i haven't used binaural beats since nearly a decade ago but i can confirm that they work (and i don't watch ASMR videos but some of them seem to play binaural beats in the background). they can be used to alter the mind in different ways, like help you fall asleep, gain mental focus or even feel like a drug high depending on the beats. it's not placebo if you have good earphones/headphones and a good audio source and if you can make your mind receptive to it (it helps to lie down in a dark room with your eyes closed).

which properties have an arbitrary
<span class="math">A (i)[/spoiler]
and its reduced row echelon form
<span class="math">rref(A) (ii)[/spoiler]
in common besides their dimensions? Can (i) and (ii) considered to be equivalent in any way?

which properties have an arbitrary matrix
<span class="math">A[/spoiler](i)
and its reduced row echelon form
<span class="math">rref(A)[/spoiler](ii)
in common besides their dimensions? Can (i) and (ii) considered to be equivalent in any way?

>>7333058
bump

>>7333058
This question is poorly defined, does the circular path have a 10m radius, diameter, circumference?

>>7333851
10m radius and 100m radius

What is the difference between evolution and natural selection?

>>7333881
Evolution works via natural selection.

Natural selection is simply stating that more fit organisms reproduce more. It doesn't say that this causes species to change over time.

>>7333902
>It doesn't say that this causes species to change over time
yes it does. the traits that make individual organisms more fit become more common within the species. individuals with less successful traits don't get to reproduce as much so those traits become less common over time.

>>7333667
They have the same determinant.
They have the same row space (the space formed by adding together the row vectors)
Same null space (same general solution)
And tons of other shit

>>7327126
>set x and y equal to 0 to get two other points

This would work if you could find two points that are on both planes... since those points would be on the line of intersection.

If I'm drawing a fbd of pic related, am I suppose to change the z values of the three forces to 4, or do they remain at 0?

when string theorists talk about there being x-dimensions, but most of them just kind of curled up, what the FUCK does curled up mean?

does it mean that the range of possible values those dimensions can take is so small we can't notice variation in them?

>>7334243
it probably means that they don't really exist

"You can solve every problem with another level of indirection, except for the problem of too many levels of indirection".

>>7334190

Bump. I've drawn FBDs where the picture I'm given is already situated at the origin, but this is the first example I've seen where A isn't situated on it.

What careers are available to me if I have two Bachelors of Science earned at the same time; one in Physics and the other in Computer Science? Is doing this worth it in the long run assuming I graduate on time?

>>7333482
Teachers get paid like shit. You're better off getting a job in in finance and making 100k+ as a quant. Once you save up enough money with that (which should be extremely easy), you can move on to something less stressful or stick with it and make a stupid amount of money.

If I jump into a pool of propane, which has a density of 493.5kg/m3, can I jump from a higher place than if I had jumped into water which has a density of 1000kg/m3, and still feel the same force in the impact?

that's where i found the densities http://www.engineeringtoolbox.com/liquids-densities-d_743.html

Is there in mathematics, the concept that a part can be bigger than the whole?

>>7329119
What uni? Mine has the same desks and chairs.

>>7332638
I've seen pictures of a dude like this a while ago. He had really long limbs but an obviously dwarf like upper torso and head.

>>7334190
The z components of the three tensions in the diagonal strings will total 1000N if we take g=10. The x and y values of the forces should total zero.

Is there a method I can use to find functions that equals sigma sums without having to use intuition and guess work?

Ex. 1^0 + 1^1 + 1^2 + ... + 1^(n-1) + 1^n = n + 1

>>7336054
well your example is simple because 1 to the power of anything is 1. so you just have 1+1+1... which adds up to 1*n + 1