Recent content by leonidas24

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    Point charge inside solid sphere

    I'm curious. Say you have a solid, positively charged sphere with a uniform charge distribution. Now suppose you place a single, negatively charged electron inside the solid sphere. How will the electron behave? I assume the electrostatic forces exerted on the electron will ultimately tend it...
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    Lagrangian, mass attached to spring on plane

    Homework Statement A block of mass m moves on a horizontal, frictionless table. It is connected to the centre of the table by a massless spring, which exerts a restoring force F obeying a nonlinear version of Hooke's law, F = -kr + ar^3 where r is the length of the spring. Show that the...
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    Does Compton Scattering Have No Effect on Electron Energy and Velocity?

    Sure. Initial photon energy: E = 2m_e So \lambda = hc/2m_e. Using the compton formula, \lambda ' = h/m_e c(1-\cos\theta_\gamma) + \lambda , with \theta = 180: lambda' = 2h/m_e c + hc/2m_e = h/m_e (2/c + c/2) = 2h/m_e c EDIT: This is ridiculous. Latex refuses to work.
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    Does Compton Scattering Have No Effect on Electron Energy and Velocity?

    Sorry, you're absolutely right. However, I'm talking about the specific case in which the photon energy E_{gamma} = 2m_e. I should have mentioned that earlier.
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    Does Compton Scattering Have No Effect on Electron Energy and Velocity?

    A quick question regarding compton scattering: if we consider the situation in which a photon incident on a free electron is scattered through an angle of 180 degrees, its energy essentially does not change. Since energy must be conserved, I assume this means there is no effect whatsoever on the...
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    Inclined Plane Momentum Conservation with Frictionless Horizontal Surface

    Consider the classical physics problem of a cube sitting atop a frictionless inclined plane. Of course, this cube will accelerate down the plane with acceleration dictated by F = mgsin(theta), where theta is the angle between the inclined plane and the horizontal surface. Easy enough. Now...
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    Schools Failing a physics class. Grad school?

    Yes, I will have to retake it. But I was under the impression that both the 'F' and subsequent grade would be included in my GPA. As I said, the final was worth 60% of the final grade so it can easily turn a solid grade into a failing one. I felt reasonably well prepared going into the exam...
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    Schools Failing a physics class. Grad school?

    Quite the opposite responses I was expecting. So failing a subject in one's major, even if only a freshman class, doesn't automatically put me at the bottom of the pile? I always assumed an 'F' on a transcript is near automatic exclusion from the top programs.
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    Schools Failing a physics class. Grad school?

    I can think of at least one negative thing about having a physics final exam worth 60% of the overall grade. Namely, you can perform well year-round only to receive a bad case of test anxiety when it matters most. I just took such an exam, and am now almost certainly (>95% chance) going to fail...
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