Recent content by Elliptic

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    Samsung vs Sony vs HTC smartphone

    Which one of these smartphones is the best? Samsung i8262 Core vs Sony Xperia M vs HTC Desire 500 Dual SIM I looked all specifications and i think HTC is first choice.
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    Sony vs Samsung LED TV: Which is Better?

    Sony 32R420 vs Samsung UE32F4000AWXXH They have similar, almost same specifications. But Sony is a little bit expensive. I need advice about specifications and which of them is better in picture reproduction and other specification.
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    Solving Scalar Curvature for Homogenous & Isotropic FLRV Metric

    Any help?
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    Solving Scalar Curvature for Homogenous & Isotropic FLRV Metric

    If I strart from this point: ## B_{\mu\nu}+\lambda g_{\mu\nu}B=0 / \cdot g^{\mu\nu} \\ R(1+4\lambda)=0 ## what next?
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    Solving Scalar Curvature for Homogenous & Isotropic FLRV Metric

    Homework Statement Find the equation of scalar curvature for homogenous and isotropic space with FLRV metric. Homework Equations ## R=6(\frac{\ddot{a}}{a}+\left( \frac{\dot{a}}{a}\right )^2+\frac{k}{a^2}) ## The Attempt at a Solution ##G_{AB}=R_{AB}-\frac{1}{2}Rg_{AB}##
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    What is the Riemann Curvature Tensor for Flat and Minkowski Space?

    Thanks. I have another problem, but i must respect the rules of forum and post a new thread.
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    What is the Riemann Curvature Tensor for Flat and Minkowski Space?

    That Riemann curvarue tensor is equal to zero?
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    What is the Riemann Curvature Tensor for Flat and Minkowski Space?

    ## \Gamma^{K}_{MK}=\frac{1}{2}\left(\partial_Mg_{ML}+\partial_Ng_{ML}-\partial_Lg_{MN} \right ) ##
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    What is the Riemann Curvature Tensor for Flat and Minkowski Space?

    Homework Statement Show that all components of Riemann curvarue tensor are equal to zero for flat and Minkowski space. Homework Equations The Attempt at a Solution ## (ds)^2=(dx^1)^2+(dx^2)^2+...+(dx^n)^2 \\ R_{MNB}^A=\partial _{N}\Gamma ^{A}_{MB}-\partial _{M}\Gamma ^{A}_{NB}+\Gamma...
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    How Do Digital Watches Utilize Physics and Electronics for Accurate Timekeeping?

    Is there any serious work with calculations and explanations about this topic? Any references? I know that that digital watch is a combination of physics(piezoelectric effect) and logic, but i need to know much more.
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    Graduate Bremsstrahlung X-Rays: Coulomb Interaction & Electron Acceleration

    1. I have problems finding the truth of this statement. The statement is cited from "book". I want to draw your attention to the following words: electron is decelerated 2. Statement: "Bremsstrahlung X rays result from Coulomb interaction between the incident electron and the nuclei of the...
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    Operating Point of a 1N4148 Diode

    I recorded statistical characteristic for sc diode 1N4148 at T=300K. How to determine operating point of diode and plot both in matlab?
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    Plotting Data in MATLAB: Two Graphs in One Plot

    how to display two plots plot1 and plot 2 in one graph? thank you
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    Plotting Data in MATLAB: Two Graphs in One Plot

    I have a set of measured data. I need to plot this in MATLAB and show two graphs in one plot. Data for first graph is : [0.35,0],[0.4,130],[0.45,400],[0.5,0.11],[0.55,34] and so on. Second graph is a function. So, how to plot sequence of data in matlab? Which command should I use?
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    Energy Gap of Intrinsic Semiconductors: Temperature Dependence

    Energy gap dependence on temperature for intristic semiconductors (Si,Ge) I need help on this topic, where to find text about this, and models that describe it (Varshni's model, linear model,...)