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  1. R

    Calculate Op Amp Gain

    I have a hard time understanding your explanation. Do you agree that my calculation are correct? If not, what are your calculations? Ratch
  2. R

    Calculate Op Amp Gain

    Why not just calculate it? The gain is calculated from the loop equation. If you want the op-amp out, then two equations are needed. The op-amp will have to work harder to supply vout because of r1. Ratch
  3. R

    Thevenin Equivelant

    Yes, I can see the subscripts now, but you reversed the direction of the independent current source and did not specify the current direction referenced by the dependent voltage source. Also you labeled the current source with two labels io and i1. That's being careless, and wastes time asking...
  4. R

    Thevenin Equivelant

    I don't know if others can read your attachment, but I sure can't. Did you check to see if it is legible? The image is way too small for my viewer. You can get the Thevenin impedance and voltage by computing or measuring the open circuit voltage and dividing by the short circuit current...
  5. R

    Ic=C x dv/dt

    Yes, and to be even more precise, the electric field is the negative gradient of the voltage between the ends of the wire. (E = - del V) Ratch
  6. R

    Ic=C x dv/dt

    Semantics is the meaning of word and descriptions. Especially in science, correct descriptions and meaning are of primary importance. That is why I dislike to observe folks using slang descriptions like [current flow = charge flow flow] . That kind of talk might be OK in a bathroom stall, but...
  7. R

    Ic=C x dv/dt

    Apology accepted. Yes, in electrical terms, current is the movement of charge carriers. Electrons do move in a random manner in a inert wire. When a voltage is applied, the electrons move by displacement, like a hose filled with marbles. One marble inserted at one end causes a different...
  8. R

    two stage amp (BJT) help

    You made a mistake calculating ib. It should be 2.88 = ib 31.97 k + ib 3.9 k 101 + 0.7 , which gives an ib of 5.11E-6 . Ratch
  9. R

    Ic=C x dv/dt

    I have been doing circuit analysis since the year one. I don't think you have anything to teach me in regard to this subject. Ratch
  10. R

    Ic=C x dv/dt

    I have exhausted my ability to explain the operation of a capacitor to you. Perhaps this analog description will help you understand. https://commons.wikimedia.org/wiki/File:Water_cap_and_diode.png . Notice that water goes into the tank and out of the tank, but does not go all the way through...
  11. R

    Ic=C x dv/dt

    I think you are measuring the charge flow released by the dielectric next to the right plate of the capacitor. No charge is passing through the dielectric. If the charge were passing through the dielectric, you would be able to sustain the charge flow value. You can't and won't do so unless...
  12. R

    Ic=C x dv/dt

    You are confused. Look at post #30 of this thread and observe to whom my reply was addressed. It certainly was not to you. I do assume you know that charge does not flow through the dielectric of a cap, but Laplace doesn't seem to understand that. He has challenged me several times about this...
  13. R

    Ic=C x dv/dt

    You say that without reading the 5th post of this thread? https://www.electronicspoint.com/threads/lpf-and-hpf.274055/#post-1652226 . Are you averring that the professors who wrote those physics books should not be teaching either. Peruse, cogitate, and learn. Come back to the side of light...
  14. R

    Ic=C x dv/dt

    Do you really mean charge flowing through the cap? Doesn't happen. If it did, the cap would be leaky and defective. What you will observe is the charge accumulating and depleting on the plates of the cap. That is much different than current existing through the cap. I thought we settled...
  15. R

    Ic=C x dv/dt

    I agree. As an aside, V/I is not Ohm's law. We can discuss that later. I disagree. Caps are a lot more complicated because they store energy while resistors do not. Resistors reduce current because they dissipate electrical energy. Caps reduce current because they produce a back voltage...
  16. R

    What is ohms law (was Ic=C x dv/dt)

    Case misstated. Current can exist in the branch containing a capacitor without the charge actually passing through the capacitor itself. This is due to the ability of the capacitor to store and deplete charges on opposite sides of the dielectric. This action can only exist for a finite period...
  17. R

    What is ohms law (was Ic=C x dv/dt)

    Then we agree that charge does not pass through a dielectric. When the explanation is well stated and proved, then it is not a crackpot proposal anymore. I do not know anyone with a full knowledge of electrodynamics who thinks that the fictional current is really a current. Max's correction...
  18. R

    Voltage dropping in resistor

    I think that your problem is not knowing what voltage is. Voltage is the energy density of the charge, defined as joules/coulomb in the MKS system. It takes energy to move two charged particles of the same polarity close together. Even more energy if they are moved closer together. Still...
  19. R

    What is ohms law (was Ic=C x dv/dt)

    Therefore, charge does not pass through the dielectric. The cap inputs current and outputs current both at the same time and at the same value. You could say that there is a discontinuity at each plate of the cap, but no net discontinuity exists. Max added the magnetic field term to "fix"...
  20. R

    What is ohms law (was Ic=C x dv/dt)

    I read through the notes in the attachment. No where does it say that conduction current exists through the capacitor. Some sources I have come across call the displacement current a "fictitious" current. It has the units of current, but it is not real current. I see no conflict between the...
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