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  1. R

    Basic Question concerning what Amps are?

    I can. Why not? There is plenty of information on the net and in textbooks that explain it. Is there some aspect of what you studied that you don't understand? Hmm. It appears that you did not study what amps are. First of all, you are using technical slang when you say current flow...
  2. R

    mesh analysis PROBLEM

    Isn't what a single loop? Ratch
  3. R

    mesh analysis PROBLEM

    Depending on the definition of a mesh, I would think that if you can write a KVL equation on it, it is a mesh. For instance, using the above numbering, and selecting loops #9, #5, and #7, one could solve for all the voltages and currents. That is because those three loops cover all the...
  4. R

    2 transistor circuit input output question.

    I, at least, think so. Ratch
  5. R

    2 transistor circuit input output question.

    Which does? The derivation or the result? No one can truthfully change the result. Show me a shorter derivation that takes Rs into consideration. Look again. I annotated that on the same line as the equation. I said Va or Vb. Yes, it is a complicated expression. Can't help that. It is...
  6. R

    2 transistor circuit input output question.

    OK, the derivation is shown below. The Thevenin resistance is shown with Rs taken into consideration. If Rs is zero, then the expression equals what you derived. Ratch
  7. R

    2 transistor circuit input output question.

    Isn't it more concise to say that the range of Vth is between -Vs to +Vs instead of a formula that has to be evaluated? Ratch
  8. R

    Complete the circuit!

    Cos(-70°) is not a negative number, Sin(-70°) is a negative number. Therefore, your calculation for R is in error. Ratch
  9. R

    2 transistor circuit input output question.

    I think you forget to calculate the Thevenin open circuit voltage. It is Vs * Rbridge/(Rs+Rbridge) where Rbridge is the resistance from the top of the bridge to the bottom. I would attack that problem a different way. I would divide the open V_ab by the short current I_ab. Ratch
  10. R

    2 transistor circuit input output question.

    My observation was not about how interesting it was. It was about what the range of Vth was. You stated that the voltage across RL could never be greater than Vth, but you never said what Vth could be. Ratch
  11. R

    2 transistor circuit input output question.

    What do you do when Vs contains a finite Rs? According to the schematic, you will have another bridge circuit.
  12. R

    2 transistor circuit input output question.

    Yes, but what values can Vth be? If just R1 & R4 both equal zero, then Vth = Vs. If just R2 & R3 both equal zero, then Vth = -Vs . So Vth can be ±Vs , which is the voltage limit of RL . Ratch
  13. R

    2 transistor circuit input output question.

    It becomes a series circuit after it is Theveninized. The two base resistors are folded into the Thevenin resistance. You don't need to apply the Thevenin or Norton method to see what is happening to the base circuit. Just keep the bottom base resistor less than 1/10 of the transistor base...
  14. R

    2 transistor circuit input output question.

    Perhaps this will illustrate better what I am saying. It is the Norton equivalent circuit. It shows that if the resistance looking into the transistor base is many times larger than the Norton resistance, then the base voltage is stabilized close to 8 volts. Ratch
  15. R

    2 transistor circuit input output question.

    What are you trying to solve in that circuit? Ratch
  16. R

    2 transistor circuit input output question.

    Being in parallel does not require a battery or voltage source. I carefully explained in post #32 that the current splits into two paths, the 2k0 resistor and the transistor base. Throw away the battery and the parallel topology is still the same. Both those paths are physically connected at...
  17. R

    2 transistor circuit input output question.

    Another way to find the Thevenin resistance is to divide the short circuit current into the open circuit voltage. 8 volts divided by 2 amps is 4 ohms. Ratch
  18. R

    2 transistor circuit input output question.

    A voltage source set to zero output and connected between two points in a circuit effectively shorts out the two points. That is the basis for finding the Thevenin resistance, right? Why is there any angst about that? Ratch
  19. R

    2 transistor circuit input output question.

    What don't you understand about parallelism? The current is present in the 5k resistor, splits into two paths via the 20k resistor and the transistor, and comes together again at ground. If that isn't parallelism, then I don't know what is. Can you articulate why you are having a problem with...
  20. R

    Complete the circuit!

    Current leads voltage in a capacitive circuit ICE. I should also mention in the spirit of pedanticalness that voltage is a scalar, not a vector quantity. A current is a vector quantity, but the direction is ignored in this case. Both voltage and current have a phase relationship with each...
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