Where Is the Error in This Power Transmission Calculation?

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SUMMARY

The forum discussion centers on a calculation error in power transmission, specifically regarding the current in transmission cables and the resulting power loss. The user calculated the current as 250/3 A based on a power of 20 MW and voltage of 240 kV, leading to an implausible power loss of 139 MW. The error was identified as a likely typo in the ohmic resistance, which should be around 20Ω, rather than the suggested 20000Ω, indicating an unrealistic distance of 2500 km from the power station to the city.

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songoku
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Homework Statement
A power station needs to deliver 20 MW of power to a city. This power is generated at 16 kV and then stepped up to 240 kV. The total resistance of the transmission cables is 20 kΩ. Show the power loss during transmission is 139 kW
Relevant Equations
P = V.I

##P=I^2 R##
The current in transmission cables = 20 MW / 240 kV = 250 / 3 A

Power loss in cables =(250/3)2 x 20 x 103 = 139 MW , which is not possible

Where is my mistake?

Thanks
 
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I think there must be a typo in the ohmic resistance of the transmission cable, most likely it is ##20\Omega##. A typical copper cable has a resistance of around ##8\Omega## per km, so if we take it that the total resistance is ##20000\Omega## this means that the power station is located 2500km away from the city...Which of course doesn't look right.
 
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Thank you very much Delta2
 
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