Recent content by mattst88

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    Equipartion Theorem rotation question

    I just had this question on my homework. Part (d) is bullsh*t, simply. It doesn't actually mean an integer when it says 'quantum number'. For me, I had 8.9e-25 for part (c), and 3.188e-54 for (b), so part (d) looked like: E_{rot} = \frac{\hbar^2 l (l + 1)}{2I} Rearrange... \frac{2...
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    Which is an example of the electromagnetic force?

    This was a question on an online homework for a modern physics class. I had two chances to answer it, but I was wrong both times, so I'm simply curious what the answer is. Homework Statement The Attempt at a Solution (a) Quarks attracted to one another is the strong force (b) A...
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    Help me understand this predicate logic question

    Homework Statement I've completed the rest of this homework assignment, but I don't understand this question. Otherwise, the section consists of proofs using predicate logic. Could anyone shed some light on what this question means? The book (and the question) is available online, here
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    Linear Algebra: Linear Independence and writing Matrices as linear combinations

    After thinking about it more, I guess that the a, b, c columns should be partitioned from the d column since I intend to write d * M4 in terms of the other matrices and their respective coefficients. This would explain the sign error from before. Can someone confirm?
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    Linear Algebra: Linear Independence and writing Matrices as linear combinations

    Going from the 4 equations/unknowns to the matrix I made a silly mistake causing the row reduced matrix to be incorrect. The (I think) correct row reduced matrix is \left[\begin{array}{ccccc} 1&0&0&3 \\ 0&1&0&1 \\ 0&0&1&1 \\ 0&0&0&0 \end{array}\right] From here, I thought I...
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    Linear Algebra: Linear Independence and writing Matrices as linear combinations

    I attempted to check this, but it appears to not work, as the equation generated is not true. -2a - 2b + \frac{4}{3}c = d Have I reduced the 4x5 matrix incorrectly or is the problem more fundamental?
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    Linear Algebra: Linear Independence and writing Matrices as linear combinations

    Homework Statement If linearly dependent, write one matrix as a linear combination of the rest. \left[\begin{array}{cc} 1&1 \\ 2&1 \end{array}\right] \left[\begin{array}{cc} 1&0 \\ 0&2 \end{array}\right] \left[\begin{array}{cc} 0&3 \\ 2&1 \end{array}\right] \left[\begin{array}{cc} 4&6 \\ 8&6...
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    How Should a Pilot Adjust Course in Wind to Maintain Direction?

    Homework Statement An airplane is traveling at 30 m/s and wishes to travel to a point 8000 m NE (45 degrees). If there is a constant 10m/s wind blowing west: A) In what direction must the pilot aim the plane in degrees? B) How long will the trip take? Homework Equations Basic...
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    Calculating Time and Distance in Lorentz Transforms: A Homework Example

    Homework Statement At x = x' = 0 and t = t' = 0, a clock ticks on a fast spaceship (gamma = 100). The captain of the ship heads it tick again 1.0 s later. Where and when do we (the stationary observers) measure the second tick to occur? Homework Equations t = \frac{t'}{\gamma} x' =...
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    When Is Kinetic Energy Equal to Rest Energy for a Proton?

    Homework Statement What is the speed of a proton when its kinetic energy is equal to its rest energy? Homework Equations K = mc^2(\gamma - 1) E_0 = mc^2 \gamma = \frac{1}{\sqrt{1 - \frac{v^2}{c^2}}} The Attempt at a Solution K = E_0 mc^2(\gamma - 1) = mc^2 \gamma = 2...
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    Differential Equations: Picard's Existence Theorem

    To find one solution: \int y dy = \int 3 dx y^2 = 6x + C y = \pm \sqrt{6x + C} So given y(2) = 0 I find that C = -12. So my two solutions are y = \sqrt{6x + C} y = - \sqrt{6x + C} Right?
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    Differential Equations: Picard's Existence Theorem

    Thanks guys. That problem was so simple. I can't believe I didn't see how to do it. ;)
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    Differential Equations: Picard's Existence Theorem

    Homework Statement y y\prime = 3 y(2) = 0 Homework Equations Solve and find two different solutions. The Attempt at a Solution F = \frac{3}{y} \frac{\partial F}{\partial y} = \frac{-3}{y^2} Where do I go from here?
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    How Is Induced EMF Calculated in a Current Loop with Increasing Current?

    Is this valid? \frac{d\epsilon}{dt} = \frac{dI}{dt} R \frac{d\epsilon}{dt} = 0.1 R d\epsilon = 0.1 R dt \epsilon = 0.1 R \int dt \epsilon = 0.1 R t And using that, plugging it into this equation: \int \epsilon dt = B \pi r^2 0.1 R \int t dt = B \pi r^2 Is this valid? Am I on...
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