Impedance

 I was asked for some insight about what electrical impedance might be. 

Below, Britannica with Google Translation:

                                                      

https://www.britannica.com/science/electrical-impedance

                                                                             

Below, an easygoing intro to calculations with complex numbers:

https://www.savemyexams.com/dp/maths_ai-hl/ib/21/revision-notes/1-number--algebra/1-5-complex-numbers/1-5-1-intro-to-complex-numbers/

Long story short: there is nothing imaginary about 'imaginary' numbers. Indeed,

i is just a symbol for the sqrt(-1). In 3 + 4i, it is the 4 that is not real, and needs to be

isolated. 

It is just that when these numbers were first enciuntered, there was a bit of discouragement

about what to do. For us, these are commonplace 😀