Quick Current and Resistance problem

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Homework Help Overview

The problem involves a high-voltage transmission line with a specified resistance and current, asking for the power loss due to resistance over a given distance. The subject area relates to electrical circuits, specifically focusing on resistance and power calculations.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to apply the formulas for power loss but expresses confusion about how to combine them effectively. One participant questions the calculation of total resistance, while another clarifies the need to consider the full loop of the transmission line.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the problem setup. Some guidance has been offered regarding the calculation of total resistance, but no consensus has been reached on the approach to take.

Contextual Notes

There is a mention of the resistance per kilometer and the total distance of the transmission line, which raises questions about how to account for the complete circuit in the calculations.

Omat128
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A problem is "A high-voltage transmission line with a resistance of 0.305 Ω/km carries a current of 1.10 kA. The line is at a potential of 800 kV at the power station and carries the current to a city located 179 km from the power station. What is the power loss due to resistance in the line?".

So the formulas i have are I^2R=power and (Change in V)^2/R. I just do not know how to put these together to save my life. I'd appreciate any help i can get. Thanks.
 
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Can you determine the total resistance of the power line?
 
Yup, i got it. Multiply the .305 times 179km, and then just plug that in the I squared R formula. And then you get the power lost. Thanks so much.
 
Not so fast there, buckaroo. The 0.305 Ohms/km is the resistance of the wire. There are two lengths of wire 179km long that make up the transmission line. The current has to circulate around the full loop, right? So what distance should you use in your calculation to figure out the total power lost by the current flowing in the wire(s)?
 

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