Recent content by Ratch

  1. R

    help with series RLC circuit

    You are wrong! I did solve a stated problem using principles found in many textbooks on Laplace Transforms. I also used a commercial program to find the Inverse Laplace Transform, as I also admitted. I did not use any AI. I hope my solution was a edification to those who wondered how to...
  2. R

    help with series RLC circuit

    Yes, I know the post is two years old and the OP has probably died by now. I solved this problem to show others how much easier Laplace Transforms make the the problem. That is because the initial conditions are carried along with the solution process and no back substitution algebra is...
  3. R

    help with series RLC circuit

    Using Laplace transforms, we can write the equation as Is1 (R1 + L1 s + 1/(C1 s)) - L1 Io + Vo/s == 0. Solving for Is1 we get Is1=(C1 (Io L1 s - Vo))/(1 + C1 R1 s + C1 L1 s^2), Usng the many computer programs we can find the inverse Laplace transform as i=(E^(-(((R1+Sqrt[-4 L1+C1...
  4. R

    Question about DC current flow

    Quote from Martaine2005: I know a man who hates ‘current flow’, he insists that ‘charge flow’ should be used instead. As ‘current flow’ = charge flow flow!. Very pedantic indeed I am the man that the above responder is referring to. If I were Lord Byron, the famous English poet, I would use my...
  5. R

    Why are these two circuits equivalent?

    The transistor won't knw the difference because the voltagdes on the base circuit and collector are the same in both cases. However, the voltage souecew on the left side will carry less current than the right side, but transistor won't know the difference.
  6. R

    The emitter has a higher potential than base ! How?

    I have seen folks really get wrapped around the axle by charge flow. First of all, when you say "current flow", you are Talking Technical Trash (TTT, T^3). Current flow literally means "charge flow flow" which is redundant and ridiculous. You should instead say "charge flow", "current...
  7. R

    The emitter has a higher potential than base ! How?

    That is absolutely wrong! A BJT by itself is a transcondance amplifier (voltage controls current), just like a vacuum tube and FET. I have heard folks say to me many times, "You can look at it two ways, voltage or current." Then they try to show that when they drive the base with a current...
  8. R

    The emitter has a higher potential than base ! How?

    The video is correct. If the emitter is grounded, and has a higher potential than the base, that means the base has a negative voltagde with resplect to ground. Putting a negative voltage with respect the emitter on the base of a NPN will cut off the collector current. Even equal voltages...
  9. R

    Second-Order Circuits

    Yes, the capacitor would energize up to 5 volts immediately due to the infinite current supplied by the step voltage source. The inductor will present an infinite impedance for an infinitesimal amount of time. The inductor will also have 5 volts across it immediately for and infinitesimal...
  10. R

    Open-circuit Req Circuit

    Ridiculously simple. Redraw the circuit. Then use any generic equation solver or pencil and paper to solve the loop equations with a 1 volt source. 1 volt gives 1/25 amp so the resistance is 25 ohms. Ratch
  11. R

    The 2 capacitor paradox

    You can ask the same question when energizing a cap and then shorting it out with a wire. Where did the energy go? It went away in a electromagnetic burst of static, arcs, and heat. Whether you de-energize the full cap through a straight wire, another cap, or resistor, the same thing...
  12. R

    Why is it PNP instead of PPN for transistors

    ----------------------------------------------------------------- Be careful what you are saying Fiber Magee. A BJT is a transconductance device (voltage controls current), not a current controls current device. It works the same as a FET or a vacuum tube. The current present in the base...
  13. R

    Determining the source voltage

    Everybody has the wrong answer. Since all the voltages are in sin(wt) format, we don't have to convert anything. All we have to do is subtract e2 from v to get the answer. Subtracting is the same as flipping the e2 phasor over 180 degrees and adding up all the x-components of phasors v and...
  14. R

    Why does a pure resistance has a an imaginary current and voltage?

    The same current passes through all components in a series circuit. Therefore, if current has "imaginary" components, all series components will "see" them. That word is a misnomer by the way. There is nothing imaginary about the shock you will receive if you put part of your body across an...
  15. R

    Bridge circuit impedance

    It no doubt is. I would compare your calculations with the Weston Lab Notes. That would be the clincher. Ratch
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