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## Homework Statement

A mining company use an electric pump with and operating voltage in the range 1.25kV - 1.5kV. There is only a 240 Vrms supply available. A transformer is used to step up the output voltage to 1.5 kVrms. The secondary winding of the transformer has 2000 turns of wire.

The first part of this question was to find the number of turns on the Primary winding of the transformer, which I have calculated correctly to be 320 turns.

The second part is thus;

The transformer has an electrical power output of 6.45kW. The underground pump is connected by 1.1km of cables to the surface. The potential difference across the pump is 1.45kV. Calculate the total resistance of the cables.

## Homework Equations

P = (V^2) / R

This is the equation I tried but it didn't work obviously.

## The Attempt at a Solution

P = (V^2) / R

R = (V^2) / P

= (1.45x10^3)^2 / 6.45x10^3

R = 325.97Ω

This result is obviously quite outlandish for the situation, and I'm really stuck as to how to progress in this question.