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    How to Determine the voltage polarity of inductor in a circuit?

    I've indicated The direction of current in second figure(Is it correct?). The current is due to charged capacitor(you can see the charge on the capacitor is Q). So what voltage equation would you write?
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    How to Determine the voltage polarity of inductor in a circuit?

    The Voltage polarity across the inductor is same as that across the capacitor since both are in parallel and the voltage across them must be same. But when Inductor, capacitor and resistor are connected as shown in the second figure what would be the voltage polarity across the inductor and...
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    Confusion regarding pinch off voltage in a JFET

    I can't figure out what actually is the Pich-off voltage of a JFET. I basically have confusion between these two definitions: Pinch off voltage is that gate source voltage at which there is no drain-source current Pinch of voltage is that 'Drain-Source' voltage after which the drain source...
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    Limit in Two variables.

    oh got it thanks man. its the y axis!! The limit comes out to be zero if i put x=1. Thanks!
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    Limit in Two variables.

    Homework Statement lim (x,y)\rightarrow(0,0) f(x,y)=2*x/(x^{2} + x +y^{2}) Homework Equations used different paths like y=k*x ,where k is a constant and y=k*x^2 The Attempt at a Solution Got an answer 2 but solution says does not exist. Can anybody convince me that why limit does...
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    Calculating integrals involving floor function

    Is it possible to claculate ∫[cot(x)]dx from x=0 to x=\piwhere [.] represents floor functon or the greatest integer function?? it seems impossible to me but can we use the properties of definite integrals to somehow evaluate the area?
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    Gravitational potential energy of a sphere of non-uniform density

    Potential energy is the work done in bringing a unit mass from infinity to the center of sphere. U=integral[from infinty to zero](F.dr.cos(x)) here x=0=>cosx=1. now f is not constant. it is different outside the sphere and also inside(non uniform density). Break the integral for outside the...
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    Capacitor charged then disconnected

    I think you're saying that we first charge a capacitor ' A' with battery 'B'. then we wait 5 secs for the capacitor to get charged and then we throw the battery 'B' and place another capacitor 'C' in its(B's) place,with our insulating gloves. I think the charge would be conserved and potential...
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    Understanding m^2 / s^2 (Speed of Light help)

    google says speed of light is 299 792 45 m/s.
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    De broglie wave equation

    i've just learnt de broglie wave equation in chemistry which tells that matter can act as wave. if an electron is moving at a certain speed(v) at which its wavelength is comparably in meters. If a football is made to move at the same speed (v),will it behave as a wave? Since Football also has...
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    What is a Photon?

    What is a photon? Does it have mass?(if no then why it has momentum) it travels with speed of light? Has it some wavelength associated with it,that can be calculated by De Broglie wave equation?
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    Work done by magentic field

    is the work done by magnetic force always zero??
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    Work done by magentic field

    Two straight current carrying conductors A and B are lying in a vertical plane as shown.The separation between them is h and mass per unit lenght of wires is λ.Keeping one wire fixed (say A),Bis raised by small hieght δh. Q-1 What would be the work done by external agent? Q-2 Will the work...