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    Question about NFS grants

    Really, I was reading things last night, and it would seem that maintenance of the equipment could fall under an indirect cost, or was I misreading?
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    Question about NFS grants

    HallsofIvy has it right, turns out I'm a horrible typist and had spent much of earlier today ranting about NSF mounts being broken :)
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    Question about NFS grants

    Hey, So I work the systems support for some university departments, and the amount of funding we get from one of the departments is in no way proportional to the amount of support we give them (they easily take up 3/5ths of our time and resources, but give maybe 1/4 of our funds). I've heard...
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    Intro QM questions

    Yeah, so basically, it's impossible to have something with zero velocity.
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    Teach HS or PhD?

    The problem with teaching at a CC though, is that it does not help fix the fact that there horrible Physics teachers in our schools, driving students away from science. Also, I know it is possible to get back into a PhD program after taking some time out. I saw my Chemistry teacher do it, and...
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    Is 3s to 2s transition for Hygrogen forbidden?

    The selection rules are not "broken" so much as supplemented when you introduce the corrections. For example, when you introduce fine and hyperfine structure corrections, you get more selection rules. One thing to note about selection rules, what you are calling "selection rules" are "selection...
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    Teach HS or PhD?

    So here's my dilemma, I think high school science teachers should be people passionate about their field, know their field and should be good enough teachers to hopefully get that passion about science inspired in some of their students (what can I say, I was spoiled by an awesome chemistry...
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    Intro QM questions

    1) This is a bit of a trick question, what you should be asking yourself, is: Is it possible for something to have something with zero velocity? (think in the quantum realm, not classical) 2) For this one, remember that quantum mechanics is all about probability.
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    Quantum Tunneling - some silly thoughts

    Well, it would be "is it possible for a few atoms of my finger tips to quantum tunnel out of the potential wells holding them into atoms, and travel in between the atoms of the wall" First, possible, highly unlikely, because if it was likely, molecules would routinely quantum tunnel apart...
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    Wavefunction for particle inside a disk

    Wait a sec, have you tried Bessel functions? It just occurred to me that if you have x=1/f, then the Schroedinger equation looks similar to Bessel's differential equation.
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    Making a grad app look good if you can't stand working in a lab?

    I'm not expecting anything more than grunt work, it's just "build a table" is the sort of grunt work I don't like :) And yeah, they're in the building phase and the supervisor (just some supervisor for the lab) and I do have a personality clash, so it's possible that I shouldn't write off...
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    Making a grad app look good if you can't stand working in a lab?

    I'm going into my 4th and possibly last year (though, if I can get my university to ignore a good deal of my useless AP credits, I won't be bumping against the 180 credit limit of my financial aid and can possibly stay an extra year, pick up another degree and bump up my GPA a bit). When you...
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    Making a grad app look good if you can't stand working in a lab?

    I guess the more important thing though, is that I need something to make my apps look good, but I can't stand working in the lab to get research experience. Is there anything else, or should I suck it up and keep going to the lab?
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    Wavefunction for particle inside a disk

    Why are you using something of this form? A_r {r_0}^{i K_r} Try using a function of this form: A e^{i x} (I just woke up, and I'm not generous enough in the mornings to offer hints about what x would be :P). Basically, I mean try something that would be sinusoidal over r.
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    Wavefunction for particle inside a disk

    Hi, Just to make sure, what are you using for you Hamiltonian? Also, what that condition tells you is that [tex] \Psi(r) [\tex] is zero at r_0 (because the particle has a 100% chance of being between 0 and r_0, so it must be zero outside r_0 and wave functions are assuming to be continuous)...
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    EM waves - energy transfer

    Why would some links fail if there are obstacles in between? Think of it this way: Why playing ultimate frisbee, why does the frisbee not get your team mate when the other team is in the way? It's because they're in the way :) Probably the best way to think of this is with the frisbee analogy...
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    Is it reasonable to go straight from general physics to classical mechanics?

    You should do fine. So long as you did decent in your into calc classes, you shouldn't be behind any of the Physics majors in the Classical Mechanics class. Usually in between the intro mechanics and intro E&M class, the Physics majors will take a modern physics class (usually a hodge-podge of...
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    Making a grad app look good if you can't stand working in a lab?

    So I posted similar thread a while ago, and it ended in me giving working at this lab a go. I've worked there two times a week since the start of the summer, and I can barely bring myself to go in. Next to my systems admin job, there is practically no reason to go to the lab. When I go to the...
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    Teaching myself calculus III

    I recommend being very careful with this, because in the case you are very successful with learning the material a head of time, you will be tempted to not go to class. If you decide to skip class, you will miss important things, you will miss information about homeworks, tests, etc, you will...
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    What to do as an undergrad if I want to go for theory?

    I think I'm interested in theoretical particle physics. I've looked at the professors in my department, but I've not had classes with any that do things I find interesting (I usually wind up with experimentalist professors). One guy is giving me a chance in his lab, volunteering for a bit...
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    What to do as an undergrad if I want to go for theory?

    Well, my question is, what would I do if I wanted to work with a theorist? Just do like a directed study with them?
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    What to do as an undergrad if I want to go for theory?

    Hey all, So, if I'm an undergrad, going onto his senior year, who doesn't have any research experience or anything shiny like that, and wants to be a theoretical physicist, what should I do? Should I just suck it up and do research in a lab?
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    Obtaining the CDSA range of Bethe-Bloch Equation

    I'm currently working on my junior project (it's basically a senior project, but for some reason you're supposed to take it third year), which is to measure the energy distribution of cosmic muons. We're doing this by measuring the muon flux that reaches a scintillator paddle below a stack of...
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    Point Charges and electric field

    Well, if that one doesn't work, what does the other possibility say? (remember that's a plus or minus sign in there).
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    Point Charges and electric field

    First let's look at Coulomb's law, just because LaTeX is pretty if nothing else: \vec{E}=\frac{1}{4\pi\epsilon_0}\sum{\frac{q_i}{r'_i^2}\hat{r}} Now, I would like to point out that r' here is the separation between the point in space we are looking at and the charged particle. Okay, right...
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    Momentum help please

    Yes, you did it right for the momentum. And in the case where the child is at rest with respect to the ice, her kinetic energy is zero, however it asks for the kinetic energy of the child-sled system, which is not zero.
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    Can absolute zero ever be achieved?

    It's fundamentally impossible to get any part of the universe to reach absolute zero, the part about needing the insulation was just a matter of hypothetical thinking.
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    Potential Difference

    Where is \frac{W}{q_0} coming from? The definition of W is usually work, which is the amount of energy required to move from one position to another, which in this case would be the difference of potential energies of two positions around the charge so: W=V_f - V_i like you had in your first...
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    Potential Difference

    I'm not sure what you're asking. Can you state it more explicitly?
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    Does anyone have solutions + questions of AP physics B free response

    Chances are your teacher does. Most AP teachers go and get copies of the old free response questions to help their students. If he/she doesn't, you can try buying a Princeton Review book, they either have old free response questions in them, or ones that have the same level of difficulty, I...
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    Properties of light

    Ah, there is no aether if that's what you're asking. Light does not travel through a medium.
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    Can absolute zero ever be achieved?

    Really in order for absolute zero to be achieved, which it isn't but hypothetically here, the matter being put at absolute zero would have to be secluded from all other matter and shielded from radiation. Even if it wasn't it just means that you'll start slowly cooling other stuff too.
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    Geiger-Müller tube

    Well, if it rains around then (don't know what part of the world you're in) you could collect some rain and measure the events per second from the fresh rain water (it was just a good ways up in the sky and exposed to cosmic rays, should have some radioactivity to it). Not difficult or anything...
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    Difference between forced vibration and combined SHM

    I had to google around for the phrase "combined simple harmonic motion" but from what I see is that combined simple harmonic motion is just a harmonic motion that is composed of two different SHM's. While on the other hand a forced vibration (I'm assuming you're referring to a Force Harmonic...
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    Can absolute zero ever be achieved?

    I don't remember the the Laws of Thermodynamics forbidding absolute zero, but either way it's still impossible to attain absolute zero. To do so would be in violation of the Heisenberg Uncertainty Principle as if a particle is at absolute zero you would be able to learn it's precise position and...
  36. P

    Constant Angular Acceleration

    I got something that was a few hundred less than your answer (can't just give it to you :) ) Make sure you're only calculating the constant angular velocity part for a time of (43-19) seconds.
  37. P

    Constant Angular Acceleration

    Only to determine the angular acceleration during the first interval: \alpha=\frac{6.9 rad/s}{3.9s}
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    U-substitution for finding v(t)

    \int{\frac{du}{a+k u}}=\frac{ln(a+k u)}{k} Integral tables are your friend ^_^
  39. P

    Two Parallel Wires( in 2 hrs!)

    If I was you I would give your best guess (ignore that you know it's "not right") and argue for points later. Chances are others having the same problem.
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    Constant Angular Acceleration

    Yup, only needed to find the constant angular acceleration in the first interval.
  41. P

    Rotational Motion Problem

    How would you do this problem if instead a ball rolled 37.0 meters in 3 seconds, and at the end of the 3 seconds it was moving at 98 m/s? Take those equations replace, x with theta, v with omega, a with alpha and you have the proper equation you'll need. The only difference between is that...
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    Free-Fall Motion Problem

    Start with a=\frac{\Delta v}{\Delta t}=\frac{\Delta v}{(\Delta t)^2} Then do the problem like you would any such problem on Earth! ^_^
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    Constant Angular Acceleration

    First find the angular displacement of the first interval is. θ(0->19) (second equation you listed, ωo = 0) Then find the angular velocity at the end of the first interval ω(0->19) (first equation you listed, ωo=0). Then find the angular displacement of the second interval θ(19-43) (second...
  44. P

    Friction and Horizontal Force

    Well when the box first starts moving the force applied will be: F_{applied}={\mu}_s F_N And it stays at that value. While moving the frictional force is: F_k=-{\mu}_k F_N So the acceleration will be equal to the net force divided by mass. F_{net}=F_{applied}+F_k={\mu}_s F_N-{\mu}_k F_N=(...
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    Two Parallel Wires( in 2 hrs!)

    If they have equal, anti-parallel currents, and it's a point that's equidistance from the wires, then the answer has to be zero. Unless you decide to ignore the fact that magnetic fields are vectors.
  46. P

    Newton's Law of Cooling of porridge

    Well, this is just a simple differential equation: y' = \frac{dT}{dt}=k (T-T_a) \frac{dT}{(T-T_a)}=k dt \int{\frac{dy}{(T-T_a)}},\int{k dt} ln(T-T_a) = k t + C T=Ae^{kt}+T_a So that's how the two equations are related. Now: T(0)=Ae^{k 0}+T_a=T_0 Where T_0 is the temperature the soup starts at...
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    Two Parallel Wires( in 2 hrs!)

    Why do you think that the Magnetic field is not zero?
  48. P

    Air Cannon Theory Help (Internal Ballistics)

    Um, okay, calm down. Also if you find my calculation in adequate, please make some constructive suggestions. And, 10%-20% is pretty big. Now, what were the equations you derived that came out to being wrong and what data disproved it?
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    Air Cannon Theory Help (Internal Ballistics)

    Oh... it's PV=const? Whoops, that changes things ^_^ I hadn't slept in a day when I started writing all those up equations. However you said you did the calc right and still go off answers. Well, you could try correcting using van deer Waals gases instead of Ideal. Also, did you minimize the...
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    Fairly Simple Gravity Problem

    The 9/11 number comes from the book (Classical Dynamics of Particles and Systems 5th Ed Thornton and Marion)
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