Recent content by vizakenjack

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    PNP Transistor voltage calculation

    For the B) part, I don't get why is it that for calculating voltage between collector an the emitter (Vce) I take into account diode on base (0.7V), whereas for part A) it's ignored? Why is Vce in part A and part B are calculated differently? Why is it that in part A voltage of 0.7V isn't taken...
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    Circuit with two voltage sources, finding voltage at nodes

    Well then Vo should be 5V-3V = 2V not 3V. Don't you see the contradiction?If I were to guess for an explanation, I'd say that for the voltage where the arrow is (in the figure of my previous post), potential difference is taken between two voltage sources. Where is for Vo Potential difference is...
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    Circuit with two voltage sources, finding voltage at nodes

    so if R1 = 1k ohm, IR would be = (5v-3v)/1000 = 2 mA, current across R1. Voltage across R1 is 5V-3V = 2V But at this point here: Isn't the voltage also 5V-3V=2V? See, I thought that voltage at that point would be the same as Vo, but apparently not ...
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    Circuit with two voltage sources, finding voltage at nodes

    So in this simple circuit, Vo = 3v?
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    Circuit with two voltage sources, finding voltage at nodes

    Wait a sec, so for negative clipper in post #7 When D1 is on it's practically a short, right? Like this: So why is Vo = -Vd + Vref. Wouldn't Vi affect it too?
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    Circuit with two voltage sources, finding voltage at nodes

    Vc is only affected by D1 but not D2, why? There's voltage across both diodes... Even though D2 is off.
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    Circuit with two voltage sources, finding voltage at nodes

    Here's another one that perplexes my mind: So why is Vo = Vi?? If D1 is off, it's basically an open, right? Like this: So Vo should be affected by Vref then, no? If you do KVL for Vo Vi + VRs - Vref = 0 ... have I got that right?
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    Circuit with two voltage sources, finding voltage at nodes

    So if voltage across open (VD2) is -2.3V (9-11.3), how come it's not affecting the voltage at Vc
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    Circuit with two voltage sources, finding voltage at nodes

    Even if no current flows, voltage would still be there, no? Infinite resistor would have a voltage across it...
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    Circuit with two voltage sources, finding voltage at nodes

    Okay, so why is it that Vc assumed to be 12v - 0.7v (D1), how about contribution from the 9v battery?? Why is this not affecting the voltage at node C? Why Vc isn't 9v - 0.7v (D2) = 8.3v?
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    Mesh current equation in matrix form

    Why would I insert something just randomly? I don't get these riddles!
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    Mesh current equation in matrix form

    But it does? You don't need to set up equation for it, because i1 = 0.001Vx
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    Mesh current equation in matrix form

    i3 -? This is how I tried to solve using cramer's rule (denominator is the determinant of the matrix, while numerator is the determinant of the modified matrix) I ignored the prefix Kilo, but the method is right. So I get a different value for i3. Does anyone know what's wrong?
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    Find voltage across resistor using mesh current analysis

    I'd like to find Vth by mesh current analysis. Mesh A and B share a current source, so they're treated as one supermesh. What's the equation for this supermesh? Also, do I ignore the loop with the open circuit? Since there's no current flowing there... 2A = ib - ia Anyway, is this the right...
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    How Do Charges and Voltages Distribute in a Circuit with Multiple Capacitors?

    "equivalent capacitance of C3" doesn't even make sense, what is it?? Ceq = C123. Q1=Q2 but it can't also be = Qeq, maybe they add up to Qeq, but Q1 < Qeq for sure. How can one capacitor hold the same amount of charge than the two capacitors one of which is the same?