Recent content by physicsphreak2

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    Flux Through Face of Tetrahedron

    Homework Statement Suppose a point charge is placed on the face of a regular tetrahedron. What is the flux through another one of the faces? Homework Equations The Attempt at a Solution I know that if the charge is placed at the center of the tetrahedron, the flux through any face...
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    Atomic Probability Densities Always Even?

    I know that for hydrogenic wavefunctions, the parity of a given state is (-1)^l . But does this mean that the probability densities for any such wavefunction is ALWAYS even? I'm trying to understand the Stark effect, and specifically why there is no first-order correction for he ground state...
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    Determine Magnetic Field from Lorentz Force

    Ok, so for the first case I should also specify that we can determine the direction of B by looking at the direction of the force exerted and using the right hand rule to deduce whether B is parallel or anti-parallel, correct? If we choose \vec{v}_1 \perp \vec{v}_2 then we should at least be...
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    Determine Magnetic Field from Lorentz Force

    Having chosen the first velocity arbitrarily, let's use your suggestion about the two cases. 1) If the force happens to be zero then we have found the direction of the magnetic field (it is the direction of \vec{v}_1 ). We can then choose \vec{v}_2 to be any vector in the plane perpendicular...
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    Determine Magnetic Field from Lorentz Force

    Homework Statement From Zangwill, Chapter 2. Suppose that the instantaneous forces on a charge, q, when it is moving with velocities \vec{v}_1 or \vec{v}_2, are \vec{F}_1 and \vec{F}_2, respectively. Without choosing a coordinate system, show that \vec{B}(\vec{r}) can be determined by working...
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    Vector Components and Translation

    Wait, excuse me? The vector components can be obtained via an inner product of the vector with some set of basis vectors. They are scalars.
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    Vector Components and Translation

    I meant coordinate system as in the set of axes defined by the our basis vectors. So, the general rule that I tried to state would be true if we be clear that the new coordinate system is described by a basis of vectors pointing along the axes-- then the components only change if the basis...
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    Vector Components and Translation

    Yes, I realize now that when I said coordinates referring to a vector I meant components of the vector. The *components* are what change. So as mathskier suggests, we can think of a rule like this: if the transformation between the two coordinate systems (not coordinates, but coordinate systems)...
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    Vector Components and Translation

    Right, this is my point: why do the coordinates NOT change due to translation whereas they DO change due to a rotation or an inversion? For instance, if I have a vector with components (1,1,1) in some coordinate system, and I then translate my coordinate system by one unit in the x-direction...
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    Vector Components and Translation

    Inspired by a question in Griffiths' E&M book (1.10), I am wondering why the components of a vector do not change when the coordinate system is translated by a constant vector. I understand that, for instance, the velocity of something moving in a coordinate system won't change if we then...
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    Laboratory Book: how do you organize it?

    Normal college-ruled notebook, but the composition book type (black marble, etc.)... Different notebook for each project, keeping them all chronologically.
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    What Is the Newly Discovered Zc(3900) Particle?

    http://news.discovery.com/space/quirky-4-quark-quantum-monste-discovered-130618.htm Do you think this is legit? How exciting!
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    How does the index of a medium affect the focal length of a lens?

    Homework Statement Suppose we have a lens of known focal length, f=100 cm. (a) If light enters the lens from air, but after the lens enters a medium with index 1.33, how far from the lens will focus? (Assume the incident light is collimated.) (b) What if there is instead air after the lens...
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