Transformer question (between substation and home)

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SUMMARY

The discussion focuses on calculating the turn ratio required for an ideal step-down transformer to deliver 100kW of power at 240V from a 10kV power station, considering the resistance of connecting cables. The primary circuit's current is determined to be 10A, leading to a potential difference of 9900V across the primary transformer after accounting for the 10Ω resistance. The power output at the secondary circuit is calculated to be 99,000W, prompting questions about the role of the secondary coil's resistance and the load represented by the home.

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Homework Statement


A power station generates 100kW of power at a voltage of 10kV. Given that the connecting cables in the primary and secondary circuit each have a resistance of 10Ω, find the turn ratio required for an ideal step-down transformer to bring electrical energy to the home at 240V.

Homework Equations



Turn ratio:
Ns/Np = Vs/Vp = Ip/Is
(s- secondary coil, p- primary coil)

V = IR
P = V^2/R = IV = I^2R

The Attempt at a Solution


For the primary circuit,
Current = 100000/10000 = 10A
Potential difference across 10Ω resistance = 10*10 = 100V
Potential difference across primary transformer = 10000-100 = 9900VI know the power across both transformer coils must be equal, so:
Power output at secondary circuit = Power input at primary coil = 9900*10 = 99000W

- What does this 99000W refer to? The power across the secondary coil or the power across the whole secondary circuit?
- Or does the secondary coil act like cell in the secondary circuit? ie. Do I have to consider its resistance?
- Does the home act like a lightbulb in a circuit? So it has a resistance?

I'm stuck here because I can't find the potential difference across the secondary coil to use the turn ratio formula.

Diagram of secondary circuit:
fks0og.jpg
 
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The power is going somewhere, so yes, assume the home load (resistance) is R. What equations can you write down?
 

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