Why do Power Lines use High Voltage?

Physics Ninja explains why power lines carry electricity at high voltage rather than low voltage.

[sunildhaul]

What a beautiful explanation as compared to the confusing explanation in textbooks. Excellent explanation.

[hdckdsadd]

I have read different forums and watched a few youtubes (in addition to my textbook readings) and the explanations seem to fall short. The issue seems to be how we are first taught about a direct relationship between voltage and current (that is, an increase in voltage renders an increase in current if resistance remains the same) and then we're taught about power lines that have high voltage and low current (because other wise we would need thick wires that carry high current [which would run the risk of overheating due to the joule effect or something or another..). So please don't explain to me the infrastructural reasons why high voltage, low current is necessary for power lines. I just need to know how high voltage, low current is even possible. I've only been studying DC so far so maybe AC has rules that would enlighten me...but I thought the E=IR formula was universal.

[CorneliuZeleaCodreanu]

Trying to give some thoughts on the actual question the viewers wanted to be answered:
How is it possible to increase the voltage without increasing the current?
Ohm s law states their are directly proportional.
I am still trying to figure it out myself, but here s what i gather from this video, which by the way is very good.
First, you notice he s using the Power formula, not Ohm s law. Why? My guess is because in this situation we HAVE to take Power into consideration, since it is given from the start. Ohm s law doesn t include power.
2) P=U*I
now, since P is a fixed known value, it means that the increase of either the voltage or current comes at the loss of the other. Basic maths.
3) there is a sort of misconception that high voltage means high current. I ve thought that to be true from the 6th to about 12th grade.
Of course, we see it is not always the case. What makes the difference (as far as i can tell) is POWER, specifically whether the value is fixed or to te to be calculated.
After all, voltage is a POTENTIAL, so whether it means or doesn t mean high current, depends on other values.
This is what i got from the video, i don t know whether it s correct or not, feel free to give me your view.
Thanks for the vid!

[anshuman]

Thanks a lot sir for explaining this concept in easiest way, it really help me a lot in learning.😊

[queensguard]

solid explanation! thank u for helping me visualise this :)

[aricwastaken]

Dr.E, i have always had problems with voltages and currents because they're basically interchangeable in equation.
The explanation you give is cool and all but i have a really big doubt wandering within me.
So hear me out. We're talking equations.
Power=Current * Voltage---(1)
Voltage = Current * Resistance---(2)
From equation (1), Power output of a given poweplant is constant . So, voltage is inversely proportional to current which basically means BIG CURRENT =small voltage and BIG VOLTAGE =small current.
Now you use (2) to convert (1) into
P=I*(I*R)
P=RI^2
But but but, here's the deal, i can also convert this equation in terms of voltage.
Which means
P=(V^2)/R---(3)
Here, the two results clash
From (3),
Power dissapated or lost = (Voltage^2) /Resistance
Here if you use high voltage, you LOSE more power
More power is dissapated.
How do you explain that?

[bravo]

Sir please explain why we can't use P=V^2/R to compare this instead of P=I^2*R

[harminderkharay]

Very simple but impressive explanation

[jamesmason]

Great explanation, thanks for the video.

[musicalsoul]

Hii.... I am in 12th ur way explanation is fantastic.... Keep going.... Love from India ❤️

[ThePaddyMak]

Is the current not dictated by the supply voltage divided by the line resistance as in Ohms Law

[cbnozawrmidas]

Need more people so spread this video more

[jadduajones]

Sometimes it takes that one video to finally understand a concept. This was it for AC current for me! I didn't ever think about the RMS of current, only for voltage. So stupid of me!

Thank you so much for this video!!!

[burt]

800kw dissipated as heat would completely melt the wire, it's not just that it's inefficient, right?

[wallsluggs]

If there was no transformer at the end and of the circuut and it was just wires, where does the rest of the power get used in the high voltage case?

[neazmakhdumhamim]

The explanation was great . Thanks brother for this helpful video. It helped me the a lot. Keep going. Take 💕💕

[chillhopnation]

But sir a question then comes to my mind that is how we put electric energy in a circuit.
The answer is giving some potential difference. Which is actually a Voltage. (Is there any other way also?) You said that you are putting some energy per second. How do you put it?
If ohms law is correct then, current should increase with increased voltage over resistance.

[YeasinRafio]

But why can't we use the ohm's law in this case?
Thanks for the amazing explanation BTW

[nestorymahunja]

Thanks for the answer now i got a clear explanation

[chance]

The theory was mostly correct. The only thing that I have issue with is that you used 120v on the secondary side of the power company's transformer. In the US, the secondary side of the transformer is always 240v in single phase. The phase only gets broken up at the branch circuit level in a residential wiring configuration. Every Breaker Panel is 240v, Every disconnect, every 240v fixed appliance.