Confusion with regards to power lines and the power lost

In summary, the conversation discusses the relationship between power, current, and voltage in a circuit. The formula for power lost is P=I2R, and by increasing the voltage, the current decreases, leading to a decrease in power lost. However, there is confusion about whether the formula P=V2/R is also applicable and if increasing voltage would actually increase power lost. It is suggested that this may be due to the type of conductors used in power lines. Ultimately, it is clarified that the voltage needed for the calculation is the voltage across the transmission cables, not the load at the end of the cables. Further explanation is requested to better understand the concept.
  • #1
Coolamebe
13
1
Ok, so the title was pretty vague, I'm not sure how to succinctly describe the confusion. Anyway, so I've learned that the power lost is P=I2R, and so by increasing the voltage, as P=VI and is constant, the current will be lowered, and thus the power lost will decrease.
I'm confused about a couple things. While my physics teacher was specifically talking about P=I2R, should not P=V2/R also give the value, and so by increasing the voltage we increase the power lost? Is this not a contradiction?
I feel like it could be remedied if the wires in power lines are not ohmic conductors and so half the math I did above is invalid.
Anyway, any help would be greatly appreciated, thank you!
 
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  • #2
The calculation relates to the power dissipated (lost) in the transmission cables so the voltage you need is the voltage across the cables. I think you are confusing this with the voltage across the load (at the end of the cables)
 
  • #3
lychette said:
The calculation relates to the power dissipated (lost) in the transmission cables so the voltage you need is the voltage across the cables. I think you are confusing this with the voltage across the load (at the end of the cables)
Can you explain this a little more in depth? My teacher explained this very superficially so I'm not too sure on this.
 

Related to Confusion with regards to power lines and the power lost

1. What causes power lines to lose power?

Power lines can lose power due to a variety of factors, such as weather events (e.g. strong winds, lightning strikes), equipment failures, or human error.

2. How much power is lost in transmission through power lines?

The amount of power lost in transmission through power lines can vary depending on the distance the power is being transmitted, the condition of the power lines, and the amount of power being transmitted. On average, it is estimated that 6-7% of power is lost in transmission.

3. Can power lines cause health problems or confusion?

There is no scientific evidence to suggest that power lines directly cause health problems or confusion. However, some studies have shown a potential link between living near power lines and an increased risk of certain health issues, but the exact cause of this correlation is still unknown.

4. How do power companies monitor and maintain their power lines?

Power companies use a variety of methods to monitor and maintain their power lines, such as regular inspections, use of drones and other advanced technology, and implementing maintenance schedules. This helps to identify and address any potential issues before they can cause power loss or other problems.

5. What can be done to reduce power loss in transmission through power lines?

There are several measures that can be taken to reduce power loss in transmission through power lines, such as using higher voltage lines, improving insulation and weatherproofing, and implementing more efficient transmission methods. Regular maintenance and upgrades are also crucial in minimizing power loss.

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