# What is the voltage at feeding end?

I am currently studying "Principles of Power System by V. K. Mehta". I am stuck at a tutorial problem from chapter 13, which is as follows:

A 2-wire d.c. distributor, 500 m long is fed at one of its ends. The cross-sectional area of each conductor is 3·4 cm² and the resistivity of copper is 1·7 μΩcm. The distributor supplies 200 A at a distance of 300m from the feeding point and 100 A at the terminus. Calculate the voltage at the feeding end if the voltage at the terminus is to be 230 V.

Here is my solution:

• Possible duplicate of What is the voltage at the feeding end? – Harry Svensson Feb 18 '18 at 13:59
• He has deleted it. – Leon Heller Feb 18 '18 at 14:46
• @SamGibson: nice crop and contrast enhancement. Why didn't OP do this? – Transistor Feb 18 '18 at 15:07
• Note the possible ambiguity or misreading in the question I read it as supplying 200A TO point C alone, PLUS 100A to point B. – Brian Drummond Feb 18 '18 at 15:26

• You know what $V_B$ and $I_B$ are so you can work out what voltage is required at C to get that.
• Now you know $V_C$ and $I_A$ so you can work out what voltage is required at A.