Recent content by GL_Black_Hole

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    Cylinder with Displaced Center of Mass Rolling Down Incline

    Homework Statement A rigid cylinder of radius ##R## and mass ##\mu## has a moment of inertia ##I## around an axis going through the center of mass and parallel to the central axis of the cylinder. The cylinder is homogeneous along its central axis, but not in the radial and angular directions...
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    Spherical Capacitor Discharging Through Radial Resistor

    So then the rest of the solution would proceed `as I've outlined? Use the expression for curl in spherical coordinates, find which component of B is non-zero and then turn the crank to find Poynting's vector and compare with the time derivative of the electrostatic energy? Regarding units I'm...
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    Spherical Capacitor Discharging Through Radial Resistor

    Homework Statement A spherical capacitor has internal radius ##a## and external radius ##b##. At time ##t = 0##, the charge of the capacitor is ##Q_0## Then the two shells are connected by a resistor in the radial direction of resistance ##R##. Find the Poynting vector and the energy...
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    Time Dilation for Moving Rectangle with Clocks at its Corner

    Yes that is what I meant by time in the lab frame. Thank you for reinforcing the distinction between the time the clock shows and the time in the lab frame for me.
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    Time Dilation for Moving Rectangle with Clocks at its Corner

    Possibly. It doesn't directly mention a reference frame. But even so am I correct in how I'm finding the time in the lab frame? Or is there a way to use the Lorentz transformations more directly?
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    Time Dilation for Moving Rectangle with Clocks at its Corner

    Homework Statement A rectangular structure carries clocks at its four corners. The clocks are synchronized in the structure’s rest frame, in which it has length L =4ft and width W = 3ft. In our laboratory frame the rectangle is moving in the positive x direction at speed v = 0.8c. As the clock...
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    Ultra-Relativistic Particle Decaying to Identical Particles

    Homework Statement Show that it is impossible for an ultra-relativistic particle with ##pc>>Mc^2## to disintegrate into two identical massive particles of mass m. Homework Equations Conservation of four momentum The Attempt at a Solution The four momentum of the ultra-relativistic particle...
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    Maximum Wavelength and Scattering Angle for Triangular Lattice

    Homework Statement A triangular lattice of lattice spacing ##a=2 ## angstroms is irradiated with x-rays at time zero of wavelength 20 angstroms at an incident angle of ##\alpha =135##. 1) What is the maximum wavelength of the incident x-rays? 2) What is the scattering angle ##\Omega## for...
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    Relativistic Harmonic Oscillator Lagrangian and Four Force

    Homework Statement Consider an inertial laboratory frame S with coordinates (##\lambda##; ##x##). The Lagrangian for the relativistic harmonic oscillator in that frame is given by ##L =-mc\sqrt{\dot x^{\mu} \dot x_{\mu}} -\frac {1}{2} k(\Delta x)^2 \frac{\dot x^{0}}{c}## where ##x^0...
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    Find ##2\theta## Values from Rotated Crystal and Intensity

    Homework Statement Consider the crystal in the attached image (https://ibb.co/ftMrBH) (a triangular lattice of white atoms with a triangular basis of grey atoms attached to them at angles of 0, 60 and 120. From a previous problem the fractional coordinates of the atoms in the basis are (0,0)...
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    Electron Diffraction Intensity and Reciprocal Lattic

    Homework Statement Low-energy electron diffraction (LEED) experiments are carried on to study a deposition of argon (Ar) and xenon (Xe) on the surface of a graphite single crystal. In the regime of vapor pressure considered, 75% of Ar and 25% of Xe are adsorbed on the (hexagonal) crystalline...
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    Orthogonal Projection of Perfect Fluid Energy Momentum

    Homework Statement Derive the relativistic Euler equation by contracting the conservation law $$\partial _\mu {T^{\mu \nu}} =0$$ with the projection tensor $${P^{\sigma}}_\nu = {\delta^{\sigma}}_\nu + U^{\sigma} U_{\nu}$$ for a perfect fluid. Homework Equations $$\partial _\mu {T^{\mu \nu}} =...
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    Change in Temperature for Stretched Surface

    Homework Statement The surface tension of a layer of water obeys ## \sigma = a- bT##, where ##T## is the temperature. Find the change in temperaure, ##\Delta T## when the area is increased isentropically. Homework Equations ## dU = dQ -dW## , ##dW = \sigma dA##, ##dU = C_A dT + [\sigma...
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    ##\alpha_P =\frac{V-b}{TV}## Find equation of State

    Homework Statement The coefficient of thermal expansion and isothermal compressibility of a gas are given by ##\alpha_P =\frac{V-b}{TV}## and ##\kappa_T = \frac{V-b}{PV}## find: a) The equation of state b) If the heat capacity at constant volume ##C_V## is constant, what is ##\delta U##? c)...
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    Show ##(\frac{\partial S}{\partial G})_Y = -\frac{C_Y}{TS}##

    Homework Statement Show that ##(\frac{\partial S}{\partial G})_Y = -\frac{C_Y}{TS}## Homework Equations ##G = H-TS, (\frac{\partial H}{\partial T})_Y = C_Y## The Attempt at a Solution ##dG = dH -TdS -SdT## and ##H## is a state variable so ## dH =\frac{\partial H}{\partial T} dT +...
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