Electric potential & potential difference

In summary, electric potential is the amount of work needed to move a charge from one point to another divided by the magnitude of the charge. It is similar to height in the gravitational field, with electric potential energy being the energy of a charge in a specific location in an electric field. Electric potential difference is the change in electric potential between two points, while electric potential is the energy per unit charge.
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Homework Statement



There is no problem but I am trying to understand the definition of 'electrical potential.' What is it. What is electrical potential difference. It is the amount of work needed to move a charge from point A to point B divided by the magnitude of the charge. What is this supposed to mean? Please give any examples. What does it mean that there is '20V worth of potential.'
 
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This isn't a formal answer. But I like to think of electricity and voltage the same way as gravity and mass. Current always wants to move from higher to lower potential. Like a rock wants to move from larger height to lower height if you drop it. If a large amount of electric charge is at a high potential, it has a lot of potential energy (positive or negative depending on the sign of the charge). Just like a large mass at great height also has a large potential energy.
 
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Indeed,

So electrical potential energy is the energy that a charge has when it is at a certain location in an electric field. Just a like rock would have above the earth.

But what is electric potential & electric potential difference. I am pretty sure electric potential isn't the same as electric potential energy. And electric potential difference, which is it? I am confused indeed.
 
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Indeed said:
But what is electric potential & electric potential difference. I am pretty sure electric potential isn't the same as electric potential energy. And electric potential difference, which is it? I am confused indeed.
If you lift a rock with mass m a height h it has the energy mgh. Now If you divide by m you get just gh. What is this? This is a number saying how "hard" it generally is to lift something on earth. It would be different on other planets since they have different g. Gravitational potential is a property of the gravitaitional field generated by the planet. Potential energy is a property of a specific mass lifted on the planet.

If you move a charge (mass) q through a potential difference (height) U it gets the energy q*U. Divide by q and you get just U. This is a number saying how hard it generally is to to move a charge in the electric field. Electric potential is a property of the electric field which some source is generating. Electric potential energy is a property of the specic charge moving in the field.

Electric potential really is similar to height, it's just that we are so used to height that it can be hard to make the connection between the two. Hope this made it clear :)
 
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Indeed said:
But what is electric potential & electric potential difference.

Electrical potential difference is the change in electric potential between two given points.

Electric potential is the e.p. difference between a given point and some assumed reference point. The location of the reference should be clear from the context of the problem.

I am pretty sure electric potential isn't the same as electric potential energy.

Electric potential energy is simply the energy or work it takes to move a known charge between two locations.

Electric potential is the e.p. energy per unit charge. It's a useful concept, since for a given electric field or charge configuration, the electric potential does not depend on the value of the charge you might choose to move between the two locations.
 

1. What is the difference between electric potential and potential difference?

Electric potential is a measure of the electric potential energy per unit charge at a specific point in an electric field. It is a scalar quantity that determines the direction in which electric charges will move. Potential difference, on the other hand, is the difference in electric potential between two points in an electric field. It is a vector quantity that determines the magnitude and direction of the electric field between two points.

2. How is electric potential measured?

Electric potential is measured in units of volts (V) using a device called a voltmeter. A voltmeter is connected in parallel to the circuit or two points in an electric field, and it measures the potential difference between those points. The value displayed on the voltmeter is the electric potential at that particular point in the circuit or field.

3. What factors affect electric potential and potential difference?

Electric potential and potential difference are affected by the distance between charges, the strength of the electric field, and the amount of charge present. As the distance between charges increases, the electric potential decreases. Conversely, as the strength of the electric field increases or the amount of charge present increases, the electric potential also increases.

4. How are electric potential and potential difference related?

Electric potential and potential difference are directly related. The potential difference between two points is equal to the change in electric potential between those two points. In other words, potential difference is the change in electric potential as a charge moves from one point to another in an electric field.

5. What is the practical application of electric potential and potential difference?

Electric potential and potential difference have many practical applications, including power generation and transmission, electric circuits, and electrostatics. They are also essential in understanding the behavior of charged particles in electric fields and how electric energy can be harnessed for various purposes.

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