How does an alternating current travel (ie100km) through cables if the direction of the current is changing?

Question

How does an alternating current travel (ie100km) through cables if the direction of the current is changing?

Answer 1

An alternating current is an oscillation. The electrons in the circuit don't necessarily respond instantaneously to a change in the direction. The changing current is more like a "distribution" of electrons changing with time, with the electrons being pushed into motion by each change in direction.  

Answer 2

It never gets where its going, but all the alternating, pushing electrons back and forth, does work on the other end. That's why it can pass energy through a transformer even though there is no DC continuity between the primary and secondary.

Answer 3

The supply voltage of the system is called the 'EMF' (Electro-motive Force) whether it's AC or DC.

The cables carrying the power offer some resistance to the flow of Electrons. This resistance causes a 'PD' (Potential Difference) across the length of the cable.

The Voltage at the Inlet end is higher than that at the terminal end.

The flow of electricity is thereby maintained.

(It's exactly the same as the flow of liquid or gas in a pipeline.

The PD (Pressure Difference) across the length of the pipeline is the driving force which causes flow within the pipe).

(Both Liquid flow and Electricity flow therefore, depend upon the 'PD' within the systems).