Help with Single Phase PE Sample Question

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wfg42438

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hello,
In the sample question below the drop across the 1-Phase Cable is considered twice.
1645303727632.png
1645303682178.png

I cant recall why this has to be done can someone please refresh my memory?
 
hello,
In the sample question below the drop across the 1-Phase Cable is considered twice.
View attachment 27075
View attachment 27074

I cant recall why this has to be done can someone please refresh my memory?
Because for 1-phase circuits, there is current going both to the load (through the supply/hot conductor) and then back to the source (through the neutral conductor). So both conductors have a voltage drop because of the current (V = IZ).

In a balanced 3-phase circuit, only the supply/hot conductor sees a voltage drop. The neutral conductor in a balanced 3-phase current has zero current because the phasor sum of the currents from 3 balanced phases is zero.
 

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