Discussion: Homework Help Thread - Finals Season!

KB.

The last thread expired for it and since school is starting that means we are getting homework. If you need any help this would be the perfect thread for it. We can all help each other so that'll be good.

Whether is college level or high school level work this should be a good thread for help since I know we have some smart people on this site

The Tutors
KB: Biology, Genetics, Zoology, Psychology, Chemistry, Physics, Anatomy & Physiology, Endocrinology
Katie: English language, literature, writing, and general linguistics
Necrolux: Physics
NCB: Biology (or anything medicine related)
SupahBass05: Calculus
Umichgrad07: Calculus, Physics, Diff Eq, Chemistry, Statistics
Miles Caufield: Biology, Psychology
iLiveMusic: English
OhRly?: Anatomy/Physiology, Biochem, Pharmacology, Psychology, Microbio, pre-med things
YSL: Communications (particularly in fashion/public relations), Media Studies, Spanish/French, History, Political Science
conseeded: Basic Anatomy/Physiology, Biology, English, Psychology, Sociology, Nutrition, and pre-med things.
Konichiwa: Latin, English, History
BabyCantYouSee: accounting and finance
CoolestPerson12: Economics, history, and English literature.
controversy: French, French Literature and Biology
HausOfGerard: English Literature, Algebra, and History

RomanNavy

I'm guessing nobody is studying European Law

RatedG²

The REAL reason I opened this thread though was because I am struggling with physics homework. It's due tomorrow and I have 14 problems which I get NOTHING of

.

If anyone could help me with question 1 it would be greatly appreciated

Quote:

Of the charge Q initially on a tiny sphere, a portion q is to be transferred to a second, nearby sphere. Both spheres can be treated as particles. For what value of q/Q will the electrostatic force between the two spheres be maximized?

It's apparently on Coulomb's law/Shell theory type things but I have no idea how to start

. The answer is also a numerical answer...wtf

Black Beauty

Thank you! I might be able to help in all sorts of math as well.

Yossarian

Quote:

Originally posted by RatedG²

The REAL reason I opened this thread though was because I am struggling with physics homework. It's due tomorrow and I have 14 problems which I get NOTHING of

.

If anyone could help me with question 1 it would be greatly appreciated

It's apparently on Coulomb's law/Shell theory type things but I have no idea how to start

. The answer is also a numerical answer...wtf

I took AP Physics, I could take a swing if you need

Sadie Saxton

I'll need this for 1050/1060

Jonathan

What a great idea for a thread

RatedG²

Quote:

Originally posted by Yossarian

I took AP Physics, I could take a swing if you need

OMG anything would be a help, even if its not the right answer because so far I have NO IDEA what to do

SupahBass05

Quote:

Originally posted by RatedG²

The REAL reason I opened this thread though was because I am struggling with physics homework. It's due tomorrow and I have 14 problems which I get NOTHING of

.

If anyone could help me with question 1 it would be greatly appreciated

It's apparently on Coulomb's law/Shell theory type things but I have no idea how to start

. The answer is also a numerical answer...wtf

Well, basically what the question is saying is you start with q1 on a sphere, transfer some value x to another sphere, treat both as particles and try to maximize force based on coulombs law. So isn't that just some calculus?

So F= kx(q-x)/r^2 needs to maximized.

RatedG²

Quote:

Originally posted by KB.

May I suggest subscribing to Chegg for your Physics homework? I took PHYS1111 and 1112 came out with an A and B respectively, but I honestly still don't understand it for the most part

I think the answer is 1/2 though which means each particle will share half of the charge.

OMG this is right

How did you do that? If you could dumb it down for dummies in physics like me lmao

EDIT: And I'll do chegg because I am also a Molecular Biology major (if I remember right on what your major is) and you seem to have the same classes as me. Physics is literally the only subject in college that doesn't mesh with me

KB.

Anyway I've taken:

A&P I and II
Physics I & II
Bio 1107 and 1108
Gen Chem I & II
Organic Chemistry I & II
Genetics
Zoology
Psychology
Calculus (Don't ask me about)

and I'm currently in Cell Biology, Ecology, and Statistics. If you need any help let me know and I'll try my best to accommodate you.

BlazingLovatic

Omg this **** y'all are talking about looks complicated. I'm gonna kill myself when I have to start doing that kinda complex stuff

Necrolux

Quote:

Originally posted by RatedG²

The REAL reason I opened this thread though was because I am struggling with physics homework. It's due tomorrow and I have 14 problems which I get NOTHING of

.

If anyone could help me with question 1 it would be greatly appreciated

It's apparently on Coulomb's law/Shell theory type things but I have no idea how to start

. The answer is also a numerical answer...wtf

The electrostatic force is given by the Coulomb inverse
square law: F = kqQ'/r²
This force will be maximized under the constraint that
q + Q' = Q, so that subsequent to charge transferral if
q = Q/2, Q' = Q/2.

then, F is maximized when both charged spheres have
equal charges: q = Q/2 and Q' = Q/2

F = k (Q/2)(Q/2)/r² = kQ²/4r²

NCB

I can help with Biology (or anything medicine-oriented).

there's a good chance i might be a little thrown off by the vocabulary (i'm not a native english speaker) but i'll do my best

SupahBass05

Quote:

Originally posted by KB.

May I suggest subscribing to Chegg for your Physics homework? I took PHYS1111 and 1112 came out with an A and B respectively, but I honestly still don't understand it for the most part

I think the answer is 1/2 though which means each particle will share half of the charge.

Wait, you're right. So basically

F(q) = kq(Q-q)/(r^2)

Take the first derivative with respect to q and set it = 0. You get that there's a maximum/minimum at q=Q/2. I'm sure you can assume it's a maximum without having to do any other tests lol.

RatedG²

Quote:

Originally posted by Necrolux

The electrostatic force is given by the Coulomb inverse
square law: F = kqQ'/r²
This force will be maximized under the constraint that
q + Q' = Q, so that subsequent to charge transferral if
q = Q/2, Q' = Q/2.

then, F is maximized when both charged spheres have
equal charges: q = Q/2 and Q' = Q/2

F = k (Q/2)(Q/2)/r² = kQ²/4r²

I see...mostly. This makes sense

. Thank you KB and Necrolux

. I may post more in here later but this should help me a lot, I am so grateful

Necrolux

Quote:

Originally posted by KB.

Anyway I've taken:

A&P I and II
Physics I & II
Bio 1107 and 1108
Gen Chem I & II
Organic Chemistry I & II
Genetics
Zoology
Psychology
Calculus (Don't ask me about)

and I'm currently in Cell Biology, Ecology, and Statistics. If you need any help let me know and I'll try my best to accommodate you.

Btw, what are you majoring in university/college ?

RatedG²

Quote:

Originally posted by SupahBass05

Wait, you're right. So basically

F(q) = kq(Q-q)/(r^2)

Take the first derivative with respect to q and set it = 0. You get that there's a maximum/minimum at q=Q/2.

nnn @ there being a calculus way to do this. I'm sure there are other problems I could do this way, I'll be asking you for help a lot too

umich

Hi all! I've finished undergrad, and I am good at:

Calculus
Diff Eq
Physics
Gen Chem
Statistics and Probability

PM me or hit me up on my wall if you have questions

KB.

Quote:

Originally posted by RatedG²

OMG this is right

How did you do that? If you could dumb it down for dummies in physics like me lmao

EDIT: And I'll do chegg because I am also a Molecular Biology major (if I remember right on what your major is) and you seem to have the same classes as me. Physics is literally the only subject in college that doesn't mesh with me

You would use F = kqQ'/r².
And it would be maximized under the condition that q + Q'=Q so that would mean that q would have to be equal to Q/2 and Q' would have to be equal to Q/2.

Honestly, that's all I remember. I remember the answer because I struggled with that same problem.