Additive synthesis wave form generator
Every randomly shaped waveform can be composed by adding one ore more sine waves signals with each a different frequency, phase an amplitude. This is also called additive synthesis. With this application you can try it for yourself. And if your browser is capable to process Web Audio API then the waveform can be made audible.
Interactive RC-series circuit
Interactive tools can be very helpful to comprehend a subject and to get a good feeling for it. The idea is to make more use of these tools. But first a concept version had to be built and tested. This article shows an example with a RC-series circuit.