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  1. #1
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    CL Circuit, Voltage on an Inductor

    Looking at the CL circuit, given an initial DC V on the capcitor at t=0. Can anyone tell me what is the V(t) and I(t) on the Inductor? Graphically and with equations
    thank you very much




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    Re: CL Circuit, Voltage on an Inductor

    At T=0, voltage across the inductor is the same as charge on the capacitor.

    The charge on the capacitor drops as its stored energy is converted entirely into current.

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    Notice that current is zero when volt readings are maximum. And vice-versa.

    Notice 90 degree difference between current and volt readings.


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    Re: CL Circuit, Voltage on an Inductor

    Brad can also post link
    to his graph for his demo version
    This one shows Voltage, Current and Power for each part.


    A good design question lists your overall requirements™ The best question deserves a better answer. ™
    ... Tony Stewart EE since 1975



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    Re: CL Circuit, Voltage on an Inductor

    As SunnySkyguy indicated, our schematics are spun off from the demo circuit of Falstad's animated interactive simulator.
    Free to download and use at:

    www.falstad.com/circuit

    ==========================

    You asked about equations. These are not quite as easy as the simple time constant formulas: C*R and L/R. Nevertheless you can still think in terms of each component's impedance to a change in voltage (in the capacitor), or change in current (in the inductor).

    There is also a formula for the voltage which develops on a capacitor, based on the current going into (or out of) it.

    The voltage on an inductor is made up (a) partly from voltage applied by neighboring circuitry, and (b) partly from its counter-emf generated by changes in current through it. It is difficult to calculate the voltage on an inductor.



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