I made a google docs file about RC circuits and hope you will review it :)

[renzoms]

https://docs.google.com/document/d/127mfGEHilpGyUfLXKS0QMOAmICfD92BGcwr-xGTOVEY/edit?usp=sharing

Why: There are some things I am certain could be described better or may be misleading/almost correct or completely incorrect. Example: current leads voltage by 90, although an RC circuit with R = 2000 and C = .001 supplied a sinusoidal voltage will not exhibit this. Hoping you can mentor me here.

I am not going to school; this isn't school related. I am going to analyze sawtooth and triangular waveform tomorrow. Thanks for anything positive, kind, and good. The notes highlighted in yellow are what I would appreciate a comment on, elaboration on, an example or you sharing personal experience related to the thing. The note highlighted in red is the example and an indication of this doesn't make sense to me anymore.

[george.b]

Current leads voltage by 90 what, platypuses, bananas, degrees?
Assuming you meant degrees: current will lead voltage by 90 degrees in a purely capacitive circuit. In an RC circuit with 2000 ohms and 0.001F (assuming you meant ohms and farads, and not stones and furlongs), that is not the case.

How good are you with complex numbers? This is all much easier to understand in the complex domain, in terms of phasors and complex impedance.

Given that a capacitor's impedance is 1/j(2*pi*f*C), a series RC circuit's impedance, Z, would equal R-j/(2*pi*f*C), with R being Resistance, f being Frequency, C being Capacitance, all units in SI, and j denoting the imaginary unit.
You may then calculate current, I=V/Z, which will yield a complex number, with a magnitude and an angle (a phasor). With this, you can see why, in a purely capacitive circuit, current leads voltage by 90 degrees, and, conversely, why that phase angle isn't 90 degrees if there is a resistive component.

[renzoms]

How good are you with complex numbers? This is all much easier to understand in the complex domain, in terms of phasors and complex impedance.

Thanks. I appreciate your comment George B.