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Physicsissuef
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Why the Earth is zero potential?
Why the Earth is zero potential (0 V)? In electrical point.turbo-1 said:In what context do you ask this? Are you asking why AC power systems use the local ground potential as the zero-point?
arildno said:His, usually.
Once again, potential is not absolute, it's relative. You can pick any point and call it "zero" and then measure all other voltages in reference to that point. The Earth is a convenient choice, since it does not change for most practical purposes.Physicsissuef said:It is truly unimaginable. I can't understand how something is zero potential or whatever. It must have some property which makes the ground zero potential. And how then the Fe have let's say 1volts e. potential, Cu 0.3 volts, or whatever. Sometimes voltage is defined as electron's pressure.
turbo-1 said:In an AC power system, ground is CHOSEN as the zero-point because it is a relatively stable reference. Ground may not be at the same electrical potential at the generating station and at a step-down transformer outside your house, but it is close enough for purposes of commercial AC transmission. Ground is not some magical zero-potential electrical state - it is a relatively stable reference that is accessible everywhere, so the power companies exploit that.
arildno said:For convenience.
belliott4488 said:Electrical potential is defined only in terms of differences
belliott4488 said:Once again, potential is not absolute, it's relative.
turbo-1 said:ground is CHOSEN as the zero-point
Physicsissuef said:If the ground is not zero potential, why when I connect R and 0, the R will burn out?
You might consider that the resistance of ground (dirt if you will) approaches zero when the current spreads out. For most intents and purposes it is works just like any other conductor.Physicsissuef said:If the ground is not zero potential, why when I connect R and 0, the R will burn out?
NoTime said:You might consider that the resistance of ground (dirt if you will) approaches zero when the current spreads out. For most intents and purposes it is works just like any other conductor.
Think of ground as a piece of wire.
NoTime said:No.
Do you understand the concept of parallel resistance?
The ground works like that.
This is why ground planes tend to involve long pieces of metal conductor buried in the ground.
NoTime said:If you have two 100 ohm resistors in parallel then the effective resistance is 50 ohms.
If you have four 100 ohm resistors in parallel then the effective resistance is 25 ohms.
Do you understand that?
This is a basic principal in electricity.Physicsissuef said:I'm not sure.
NoTime said:This is a basic principal in electricity.
Perhaps one of your instructors can help you select a book, in your language, that will help you understand.
Physicsissuef said:Ok, I checked my dictionary and understand what do you mean by the efficiency. So what next?
Physicsissuef said:Yes. Can you give me the end of your analogy?
Do you want to say, that the Earth have no resistance?NoTime said:If each cubic cm of dirt has a Resistance of 100 ohms what is the Resistance of the number contacting 10 meters of ground plane?
Consider that this situation has 3d geometry so each row out connects with additional parallel chunks of dirt.
Yes, I read it, but can't understand how they managed to get zero. You say that the Earth potential can be manipulated?Integral said:Physicsissuef,
Please make an effort to ask a complete question. Your drawing is nearly indeciferable, could you make an effort to make a clear drawing and ask a specific question about your difficulty.
I will further ask that other members refrain from responding until we have a clarification of the question.
Have you read my post #15?
Daz87uk said:Why Zero, Simply because its under our feet and its convenient. The Earth has a magnetic field this effects Electrical equipment and conductors around us, but as how to define it as Zero simply Joining to Disimular Conductors together makes them Equal or Zero potential. Same theory as Farendays Cage, you're in the potential Zone so you will not get an electric shock. Step out of this zero potential and your toast. Electricity wants a simple way to Earth and by Earth we mean Zero, become that Zero and it will simply ignore you. Correct me if I am wrong but that's generally how it works.
The earth is considered to have zero potential because it serves as a reference point for measuring the potential energy of other objects. This means that the potential energy of an object at the surface of the earth is equal to its gravitational potential energy, which is zero at that point.
The concept of zero potential is closely related to the earth's gravitational field. The earth's gravitational field is what gives objects their potential energy, and the surface of the earth is considered to have zero potential because it is the point where an object's potential energy is at its minimum.
Yes, the earth's zero potential has a significant impact on the behavior of objects on its surface. It is the reason why objects fall towards the ground when dropped, and why they have potential energy when lifted above the ground. It also plays a role in the movement of tides and the orbits of satellites around the earth.
The concept of zero potential is used in scientific calculations to determine the potential energy of objects in relation to the earth's surface. It is also used to calculate the work done on an object when it moves from one point to another in the earth's gravitational field.
The earth's zero potential is not constant and can change depending on the location and altitude. It is generally considered to be constant at the surface of the earth, but it can vary at higher altitudes or in areas with different gravitational forces, such as near mountains or in space.