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Update: He didn't respond to the 1st email. So I sent him a 2nd email a week ago and he hasn't responded. Any advice?

Ok I sent him an email & he didn't respond. Should I try again or take this as a sign he's too busy to have me as a grad student?

I know that its for boosting minorities in physics & not for giving people with other issues a chance. However I didn't fit purpose and applied anyway. A masters program from here took me in. Just saying it could be an option after he strengthens his foundation. Although the above program does...

Ok thanks! I'll definitely contact him. Another question. I'm looking to transfer there because it seems less competitive than say, Harvard/Columbia. Also, if I do get there and work under him, since he's a world-renounced researcher (one of the highest cited in world), it seems that having his...

I didn't contact him yet. I think that since he's busy (he's one of the highest cited scientists in world has 15 grad students and is professor emertus at Berkley), he won't have time or my just tell me to just apply. Should I still contact him? Other options?

Hello, I'd like to work in the above named center at the University of Georgia in Athens, Georgia under Dr. Henry Schafer. However, he's a professor in the chemistry department. I'm guessing if I go in the university as a physics graduate student I can't have him as a Ph.D advisor. However, is...

Try the APS Bridge Program: https://www.apsbridgeprogram.org/about/students.cfm

Oh I forgot something: df/dx = f'(x+vt)*dx; df/dt = f'(x+vt)*v*dt So KE + PE = μ/2[(f'2(x+vt)*dx+v2*f'2(x+vt)*dt] = 0.5*μ*(1+v2)*f'2(x+vt)*(dx+dt) Forgot to add primes in front of f's to indicate derivative.

df/dx = f(x+vt)*dx; df/dt = f(x+vt)*v*dt infinitesimal energy = KE + PE = μ/2[(f2(x+vt)*dx+v2*f2(x+vt)*dt] = 0.5*μ*(1+v2)*f2(x+vt)*(dx+dt) Total energy = ∫0.5*μ*(1+v2)*f2(x+vt)*dx I'm guessing dt goes to zero since we're integrating with respect to space/over entire spring & not time. Is this...

Ok, so I figured out that dψ/dx = dψ/dt. So infinitesimal energy = μ/2(2V2*(dψ/dx)2)dx. Since v2 = T/μ, infinitesimal energy = T*((dψ/dx)2)dx. Now I integrate to get total energy for whole string: total energy = ∫T*((dψ/dx)2)*dx. Limits of integration are ±∞. I don't see how they go from this to...

Post this in the advanced physics homework section

Homework Statement There's a string with tension T & mass density μ that has a transverse wave with ψ(x,t) = f(x±vt). f(x) is an even function & goes to zero as x→±∞ Show that the total energy in the string is given by ∫dw*T*((f'(w))2; limits of integration are ±∞ Homework Equations The...

The Attempt at a Solution 1) ∫-∞ ∞δ'(x)*f(x-a) 2) = ∫δ(x)*f(x-a)dx-∫f'(x-a)*δ(x)dx 3) = f(-a) - f'(-a) Went from 1st to second by integration by parts Used integral definition of delta function to go to 3rd part Made above easier to read

Homework Statement Prove the following '()( − ) = −′() ∫-∞∞δ'(x)*f(x-a) = -f'(a) Homework Equations ∫-∞∞δ'(x-a)*f(x) = f(a) The Attempt at a Solution [/B] ∫-∞ ∞δ'(x)*f(x-a) = ∫δ(x)*f(x-a)dx-∫f'(x-a)*δ(x)dx = f(-a) - f'(-a) Went from 1st to second by integration by parts Used...

Homework Statement https://1drv.ms/b/s!ApJAu5EMYb4JgpYy68UWlGVzp0PVLQ Problem 21 Homework Equations [/B] x1 = Aeiw0t + 3Be2iw0t x2 = 3Aeiw0t - Be2iw0t The Attempt at a Solution [/B] At t = 0 both masses at equilibrium so the above equations simplify to: 0 = A + 3B 0 = 3A - B Thus B =...

One more thing: I still don't know how they jumped from the 2nd to last line to the last line in this problem (in the answer I mean).

Oh! I was just guessing. I forgot to tell you, I basically solve this using loop current method & current equalities. Here's a link to my teacher's answer if it'll help. https://1drv.ms/b/s!ApJAu5EMYb4JgpYqh2SQVlgB1Tevvw

Wow, it seems the replies imply that you are not given enough support from the school for this class. Out of curiosity, does this happen a lot in your school district & in the U.S.A in general? If what I said about support is true & curriculum is undoable, maybe ignore the entire curriculum &...

https://1drv.ms/b/s!ApJAu5EMYb4JgpYy68UWlGVzp0PVLQ -- Here's the link if it helps you see better. problem 18b. I would not assume anything is equal to another unless the problem explicitly says that

So this means that we can't use their complex form because whatever operators we use on them are only linear? Also, is another way to understand this is that since power & voltage are real, that means we must take their real part when doing operations with them?

Yes, I know that they plugged in Q(t) = Aeiwt into the differential equation & found A. Then they took Re(Aeiwt) & plugged that into energy equation for part a. I still don't understand this: Why can't you plug in Aeiwt into the energy equation as opposed to its real part?

https://1drv.ms/b/s!ApJAu5EMYb4JgpYqPvc50rCWNa3jiw problem 13 part a & before that

Homework Statement Just problem 19C. Homework Equations P=IV=Ieiwt*Veiwt. T The Attempt at a Solution P = IVe2iwt=IVcos(2wt). What did I do wrong?

Homework Statement Just help me with 18 b. Homework Equations V1 = c1I1Z1. Same for V2,3,45. V = V1+V2+V3+V4+V5. V/I=Z=impedance. The Attempt at a Solution Maybe because of symmetry Z1=Z2 & Z3=Z4. Perhaps Z5 takes out one of the branches? Can I get a hint?

Here's the entire answer. Why doesn't my approach work?

I'm not doing any internships either. For the summer I'm doing the following: 1) Doing a sales/marketing job. I'm going door to door & setting appointments for doors,gutters, etc. Money os good, but as a poster alluded to, soft skills are important. I'm developing marketing/communication skills...

Well in the answer the teacher gave, he took the real parts of Q(t) & dQ/dt. He then plugged them into the E formula above. Why does this work and my approach doea not (I take the real part AFTER equations are plugged in).

Homework Statement Homework Equations Q(t) = Aei(wt+Φ); dQ/dt = i*w*Q(t); E = (L/2)(dQ/dt)2 + Q2/2C i = √-1 E above is average energy The Attempt at a Solution When I plug in Q(t) & dQ/dt into equation above (E) I get: A2L/2(w02-w2)cos[2(wt+Φ)] w02 = 1/LC After I plugged both of them in...

Homework Statement Lets say f(x) is a solution to TISE. If it is, why is its complex conjugate f*(x) a solution too? Homework Equations TISE = time independent Schrodinger equation The Attempt at a Solution ?

=So for A1, let's say that the charge is closer to that than A2. Because E1=(charge density *A1)/R1^2 and E2=(charge density *A2/R2^2). We can say that magnitude E1=magnitude E2? So for A1, even though the charge is closer to that area, A1<A2. For A2, even though the charge is farther away from...

Homework Statement If a point charge is inside a Gaussian sphere but is off center, why is its electric field still Qenc/(e0*4*pi*r^2)? Homework Equations surface integral of E*da=Qenc/e0 The Attempt at a Solution If we draw cones out from the charge. the 2 surfaces from the cones'...

But since you don't have the right answer, you don't know if the equations you derived are right. So, how can you know if you have the right approach to begin with?

The end of the chapter things are divided into 2 sections: 1) Problems-these have detailed solutions 2) Exercises-these have no solutions whatsoever this helps? The main question I have is if it's worth doing the exercises (#2 above). Since they don't have the answers in the back, is it...

So you're saying that I should do the exercises that deal with the same subject as the problems I was struggling with. But, how do I know if I' got them right? There's 33 problems (with soln) and 50 exercises (w/o soln).

Hi everyone, I'm studying E&M using Purcell & Morin's textbook. The end of chapter exercises are divided into problems (has detailed solutions) and exercises (no solutions whatsoever). I know I should do all the problems, but is ti worth it doing the exercises. I mean, if I try the problem...

Homework Statement y=[(1+y^2)^1.5]/[2(y+sqrt 3)^2]; solve for y Homework Equations see above The Attempt at a Solution I tried to use algebra to solve it, but I can't. The textbook says it can be solved numerically or by iteration. By numberically I think it means algebraically. But I don't...

Ok, but it says this book is for juniors and seniors taking intermediate level e&m. Is there any textbook as rigorous as the one I mentioned and is for freshman/sophomore level e&m?

Please help me find a similar textbook to the one below. Note that I'd like it on the internet and free. Thanks! "Electricity and Magnetism", E. Purcell & D. Morin, 3rd edition. From what I've heard, it's a textbook for an introductory electricity and magnetism class. Note that it has some...

The reason I ask this is because I met with my advisor this week. He told me that if I want to go to grad school, taking just the required class and getting As is better than adding a minor or double major and getting Bs. Is this true? The answer to this will determine how I select my classes at...

Which is better: 1) Majoring in physics, minoring in computer science, and getting Bs and some Cs 2) Just majoring in physics and getting As and some Bs. Also, how do you pay for grad school? If your're accepted in gradschool, do they pay for your living and tuition, or do you have to pay for...

What this user said definitely resonated with me. Maybe I should look into the past to answer my questions. Years ago, I was doing mental math. I was trying to figure out how to multiply 23*67 in my head for instance. Recently I figured out that 23*67=(20+3)*(70-3). After years and years of...

correction Shoot! I'm sorry! T=r*F. I got it backwards! If I plug in the right equation, the first equation will eventually turn into 0.5*m*(r^2)*(ωf^2)=I*(ωf^2).

response to ehlid How is it wrong? Force is torque times radius, is it not. Oh, I can't use scalar multiplication on this. Do I have to use the cross product: F=t x r?

Homework Statement How to derive W=(.5*I)*((ωf^2)-(ωi^2)) from W=τ*(θ) Homework Equations The two equations seen above (big W is work; little w is rotational velocity, τ is torque, alpha=rotational acceleration). s=r*θ a=r*(alpha) (ωf^2)-(ωo^2)=2*(alpha)*(θ) F=r*τ F=ma...

response I guess you need to watch someone life weights to learn the technique. However, at some point you have to lift weights. I guess you need both, but mostly #1. I am doing #1. However, my question is which is the correct way to do #1. Is spending hours and hours on a single problem...

replying Ok guys, Thanks for your posts! The reasons is I sometimes spend 2-3 hours on a single problem (in physics 1: classical mechanics). I sometimes think that those hours are wasted b/c I've heard spending hours and hours on a single problem is time gone down the drain. Based on my own...

Which is a better way to do physics? 1) Do a complicated problem, spend hours and hours on that single problem until you solve it. 2) Try to do the complicated problem for 5-10 minutes; look at the answer and try to understand the answer for 5-10 more minutes. Then, move onto another...

question for lazer So, basically you (thegreenlazer) mean this: Let's say that you're examining what the initial height of the ball was when it was falling due to gravity. What happens to it. Initially, it has potential energy. As it falls, that potential energy turns into kinetic until all...

question for lazer So, basically you mean this: Let's say that you're examining what the initial height of the ball was when it was falling due to gravity. What happens to it. Initially, it has potential energy. As it falls, that potential energy turns into kinetic until all the energy right...

other ways Alright, thanks. It looks like I'm on the right track. Can someone tell me of other ways to build a conceptual understanding of physics besides doing problems? Thanks