Recent content by noranne

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    How Do You Derive the Lagrangian for a Pendulum on an Oscillating Cart?

    Homework Statement A simple pendulum (mass M and length L) is suspended from a cart (mass m) that can oscillate on the end of a spring of force constant k. Write the Lagrangian in terms of the two generalized coordinates x and \phi, where x is the extension of the spring from its...
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    Transforming Equations for the Simple Harmonic Oscillator

    Yeah, one of my friends just told me "Didn't you get Prof's email? That's a typo!" Gr. I KNEW that I wasn't doing it wrong. Thanks!
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    Transforming Equations for the Simple Harmonic Oscillator

    Yes, I know, but that still doesn't help me get E*e^(wt) in terms of cos and sin.
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    Transforming Equations for the Simple Harmonic Oscillator

    I guess this is maybe more algebra than calculus, but it stems from a calculus problem, so I'll stick it here. The problem is: In the case of the simple harmonic oscillator the solution [to the EOM] may be written at least 3 ways x(t) = Acos(wt) + Bsin(wt) = Ccos(wt + del)...
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    Parseval Relation/Fourier Series

    We got it...turned out we were just confused by the phrasing, and the problem was actually really easy. Go figure. Thanks!
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    Parseval Relation/Fourier Series

    Homework Statement Slope-matched parabolic sections. Consider the function of period 4 defined over the interval [-2,2] by the equations: f(t) = 2*t-t^2 for 0<t<2 and f(t) = 2*t+t^2 for -2<t<0 It has a Fourier expansion \sum_{m=0}^\infty \frac{32}{\pi^3*(2m+1)^3} sin((2m+1)...
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    Solve Uniform Acceleration: Find a = -12.4872 cm/s^2

    The value you're using for X is wrong—note that the object starts to the right of the origin and ends at the left for this period of time.
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    Calculating the Age of a Mummy Shroud Using Carbon Dating - Step by Step Guide

    In present day, Co is 15.2, which is what it was when the shroud was first made. This value decreases by half every 5730 years, so the formula to use would be C_{o} (.5)^\frac{t}{T} = C where Co is the initial amount of carbon, C is the amount of carbon after t years, and T is the half life.
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    Junior at the Naval Academy, physics major

    2. I could attempt, but not many people get to do that. Usually very good pilots go on to become astronauts, and I don't want to be a pilot. 3. I definitely have choices. :) I actually don't even know if I could go to the Naval Observatory, maybe for a shore tour for a more senior officer...
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    Struggling with Solving a Diff Eq? Get Expert Help Here!

    I guess I didn't mention that I was given two BC ( y(1)=1 and y'(1)=0 ) and I was able to solve for them. And my final answer checks out. Phew.
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    Struggling with Solving a Diff Eq? Get Expert Help Here!

    Success! y = \sqrt{-x^2 + x + 1} Thank you SO much! No one in my class has been able to get that, we've been frantically IMing back and forth all night.
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    Struggling with Solving a Diff Eq? Get Expert Help Here!

    Ohh, okay, I see how that's different than the substitution I was using. Let me try this again (again).
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    Struggling with Solving a Diff Eq? Get Expert Help Here!

    Yeah, but I can't separate it! Or rather, I can separate it, but I get completely unworkable results. It tends to fall apart when I get to -ln(u^2 + 1)/2 = ln(y) + C
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    Struggling with Solving a Diff Eq? Get Expert Help Here!

    Sorry, yeah it's an ODE. I know the notation is a little weird but it's the easiest way for me to type it.
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    Struggling with Solving a Diff Eq? Get Expert Help Here!

    Never expected to be pleading for help so soon, and especially not on a differential equation, which I usually am good at. But for whatever reason, I cannot solve this problem: y*d(y,x,2) + (d(y,x))^2 + 1 = 0 Any help would be greatly appreciated! ETA: I know I'm supposed to substitute...
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