Recent content by pepediaz

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    What would be the Wigner-Seitz cell of this lattice?

    I know WS cell only contains one lattice point, so we would have to trace bisectors, and obtain some kind of irregular shape. Anyways, I wanted to check if what I did is okay. It is considering a fictitious point as the center of the (non-primitive) unit cell, which would be one of those...
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    Why bulbs and LED diodes keep glowing after being switched off?

    First of all, thank you all for your responses, they are giving me a lot of insight in this issue. So, as I can observe, the phenomenon is mainly due to the materials and the little capacitances the current finds on its way. I have thought about hypotetical physical phenomena: magnetic...
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    Why bulbs and LED diodes keep glowing after being switched off?

    Thank you all, now I can imagine better how this phenomenon works. Is there a way to estimate the currents and power consumption when the circuit is open?
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    Why bulbs and LED diodes keep glowing after being switched off?

    I have plot the circuit the best I could. The cable is 10 m long, and the two insulated wires have each one a section of 1.5 mm•mm. Let's suppose there is no capacitance. Changing the position of the bulbs is indifferent.
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    Why bulbs and LED diodes keep glowing after being switched off?

    But it's a circuit I have made, with a long cable and a battery. The effect of dimly lighting after being switched OFF happens. Both for bulb and LED. I don't know why.
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    Why bulbs and LED diodes keep glowing after being switched off?

    The bulb/LED is connected to a long cable consisting of two insulated wires. I want to know how is this phenomenon happening in a physical way. I mean, not referring to the quality of used materials. I suppose that for the bulb, it happens kinda Joule effect, and when the circuit becomes...
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    Bragg curve -> observing dependence on velocity

    Ah okay, I think that speed (or kinetic energy) is to look when studying stopping power. We see that matter absorbs and scatters alpha particles that traverse it. I can also see that Fig.4 is the gradient of Fig.3 , and recognise the shape of the functions. The key on this is that stopping...
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    Bragg curve -> observing dependence on velocity

    We would have the Fig.3 as a decreasing line function and Fig.4 as a constant value. But how do we know from Fig 3 or 4 that it is velocity and not other parameter what creates dependence for dE/dx ?
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    Bragg curve -> observing dependence on velocity

    ah okay, so it is because at equal displacements (the markers on abscissa), the plotted function starts kinda lineally, but then decays steeply. As a result, energy decreases steeply -> the squared velocity decreases steeply -> the stopping power increases, isn't it? Thanks!
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    Bragg curve -> observing dependence on velocity

    We can read: "The velocity dependence of the stopping power, increasing with decreasing velocity, is obvious from Fig.4". I know why the stopping power depends on velocity as Bethe equation states, but I do not know how I can observe that dependence on a Bragg curve.
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    Bethe formula dependence on charge of the material

    I think that it is a trick question and that the answer is that given dependence does not exist. Could anyone tell me if I am right?
  12. P

    Can't understand ket notation for spin 1/2

    I can't why there are four elements in each ket instead of only two
  13. P

    Why Does the Triangular Net Exhibit Three-Dimensional Properties?

    The answer for triangular net is -3NJ, so D=3, although I think that it has two dimensions in spite of every atom having three near neighbours.
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    Erasmus studentship at University of Warsaw

    I have been said that it is contemplated to provide foreign students with resources in English, so i suppose that I will do everything in English.
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