Recent content by nd

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    Wavefunction expansion coefficients

    I'm working in Liboff, 4e, QM, page 114, problem 4.35. An electron in a 1-D box with walls at x= 0,a is in the state \psi(x) = A for x\in (0,a/2) and \psi(x) = -A for x\in (a/2,a). What is the lowest possible energy that can be measured? From my understanding, the answer to this question...
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    Uniformly Charged Cone - Potential Difference

    I take \textbf{r}(t,u)=t(\cos u,\sin u,1) to be a parametrization of the cone. The norm of the fundamental vector product is (this can be easily checked) \| \frac{\partial \textbf{r} }{\partial u} \times \frac{\partial \textbf{r} }{\partial t} \| = \sqrt{2} t As you can tell by my...
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    Uniformly Charged Cone - Potential Difference

    We have a right circular cone of base radius a and height a with a uniform surface charge sigma. I want to determine the potential difference between the apex of the cone and the center of the base (this cone doesn't have any charge on the base). My plan of attack for the problem was to...
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    Power Series Solution (SE)?

    Yes, I got something similar to that. I was working out a problem where the point was to show that things get too messy when you try to get a solution directly. But that recursion formula seems just fine to me. That's what I originally thought too.
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    Power Series Solution (SE)?

    Here's our equation: \frac{d^2\psi}{du^2}+(\frac{\beta}{\alpha}-u^2)\psi=0 This is the SE for the simple harmonic oscillator. My text goes through an elaborate solution to this DE and ends up resorting to a power series solution, not for psi, but for H, where \psi=H(u)e^{-u^2/2}. The text...
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    Predicting Energy Quantization in CM Systems

    Are there any systems in CM where quantization of energy is predicted?
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    The Mystery of the e Series: Uncovering Its Name

    \displaystyle e=\sum \limits_{n=0}^{\infty} \frac{1}{n!}, if I remember correctly. What are you interested in learning about series? Most series, as far as I know, don't have names.
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    UM: No Calculus in 200 Level Physics Courses - Is This Normal?

    What is the name of the course?
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    Losing a solution of a 1st order ODE?

    Your initial condition y(0)=2 seems to imply that c = 0, not -1=1? You can preclude y=-2 simply by noticing that it fails to satisfy the initial condition.
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    Calculating Capacitor Potential Difference and Resistance for 12V Battery

    The capacitance will of course cancel since we are given no information about the capacitor itself. The energy store in a capacitor is U = \frac{1}{2} CV^2. The problem at hand states \frac{1}{2} C_1V_1^2= \frac{1}{2} C_2V_2^2. You are looking for V_2.
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    Calculating Capacitor Potential Difference and Resistance for 12V Battery

    For the third one, http://www.sengpielaudio.com/calculator-ohm.htm. Your first question is unclear. For the second one, can you tell me the energy in the capacitor without the dielectric? Qualitatively, do you expect the required voltage to be more or less than the case with k=1? Do you have...
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