How will calculate the reactive power demand? & another one is at how much distance is sufficient at which votge drop is not starting .(in case of High tension & LT lines.
It depends on the capacitance and inductance of the distribution system and whatever is connected to it at any time, and also the system frequency.
<how much distance is sufficient at which voltage drop is not starting>
In circuits where no superconductor is present a voltage drop is always there, as conductors have resistance.
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