Power lost in transmission lines

AI Thread Summary
A power station generates 1000MW of electrical energy, with 7% lost in a 500kV transmission line, leading to confusion over the line's resistance. The initial calculation using P=I²R resulted in an incorrect resistance of 268 ohms, while the expected answer is 17.5 ohms. The voltage drop along the line is crucial for accurate calculations, which the poster initially overlooked. After recalculating the power lost and total current, they found discrepancies, leading to a resistance value that seemed too small. Clarification on the voltage drop and correct application of formulas is needed to resolve the issue.
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Homework Statement



A typical power station produces 1000MW of electrical energy. Seven percent of the power is lost in a 500kV transmission line. Whats the lines resistance?

Homework Equations



P=I2R

The Attempt at a Solution


Thought this problem was simple but I keep getting it wrong.
P=I2R so P=V2/R
7 percent is lost @ 500Kv
so 0.97*1000*106 = (500*10^3)^2/R
R=268ohms but the actual answer is 17.5 ohms?
Thanks
 
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The V in V^2/R is the voltage drop along the line - which you don't know
Work out the power lost, then the total current, then try
 
So P=VI
total I: 1000*10^6/500*10^3=2000A (that can't be right can it, its huge)
0.7*1000*10^6-1000*10^6=9.3*10^9W (power lost)
9.3*10^9=2000^2/R
R=4.3*10^-3ohms- that's too small now?
btw thanks for replying
 
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