Why can current flow from power line to earth ground?

[William White]

I think you always had it; just over-thinking.

As an engineer, you will soon learn when to make the simplifications necessary -
ie when to think of the wire as "ideal" with no resistance and when to think of it as a very long, but low value resistor.

 

[DoobleD]

I probably won't because I'm not a "real" student, and not trying to become an engineer! :) I am an online learner, using some free resources (mainly MIT OCW) to learn physics. I graduated in computer science. It'd be nice to switch field someday though!

 

[William White]

good for you, those MIT courses are excellent.

If you are interested in circuit theory, then try and pick up this book
https://www.amazon.com/dp/0415662869/?tag=pfamazon01-20

Its aimed at HNC/HND Engineering level students (Higher Nationals are vocational programmes which are equivalent to the first and second years of an engineering degree); and is the bible for circuit theory. It really starts at the basics, and goes through more complex problems and covers everything you will ever need to know unless you become a specialist.

 

[DoobleD]

Ok, I've looked a at it a little and it seems indeed fairly awesome, so I got the e-book right away. :D And there is a chapter about transmission lines! Thanks again.