# Electric Potential Differences

• daimoku
In summary, the conversation discusses electric potential differences, specifically in a scenario where an electron is moving from point A to B along an electric field line and the electric field does 2.44*10^-19 J of work on it. The question is then posed to find the electric potential differences from VB->VA and VC->VA. The formula V2-V1= -Welec / q is suggested, but it is pointed out that for equipotential lines, there is no change in potential energy. The second part of the question involves using the equations V2-V1= -Welec / q and V2-V1= - integral E*ds, but it is determined that only the first equation is useful in this situation
daimoku
[Solved] Electric Potential Differences

When an electron moves from A to B along an electric field line in Fig. 25-26, the electric field does 2.44*10^-19 J of work on it.

http://tinyurl.com/2s34zk

Find the electric potential differences from VB->VA and VC->VA.

I think the potential difference is the same for each but I'm not positive. I'm not sure what formula to use either...V2-V1= -Welec / q or V2-V1= - integral E*ds ? If someone could get me started in the right direction I think I can figure out the rest. Thanks for your help!

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Your guess is correct for the first part. The reason why(which is important to understand!)is in the names. If you move in the direction of an equipotential line, you're not changing your potential energy, and hence there's no work being done, in going from one equipotential to another, you change your potential energy by that much, no matter the path(ever hear that electric fields are path indepedent?)

As for the second part, I think both equations are true, but only one is of any actual use to you. Which is it, considering what information was given?

I think that the only thing you need to do is divide the work by the charge of electron, since potential is defined as work done on one coulomb charge. the potentials between AB and AC are the same.

Thanks for confirming my suspicions. The negative sign was throwing me off. Found the electrical potential difference for both parts to be 1.525V. Thanks again!

## 1. What is an electric potential difference?

An electric potential difference, also known as voltage, is the difference in electric potential between two points in an electric field. It is measured in volts (V) and represents the amount of work needed to move a unit of electric charge from one point to another.

## 2. How is electric potential difference different from electric potential?

Electric potential is a measure of the electric potential energy per unit charge, while electric potential difference is the difference in electric potential between two points. In other words, electric potential is a scalar quantity, while electric potential difference is a vector quantity.

## 3. What causes electric potential difference?

Electric potential difference is caused by the presence of an electric field. In order for there to be a difference in electric potential, there must be a difference in the distribution of electric charges or a difference in the strength of the electric field between two points.

## 4. How is electric potential difference measured?

Electric potential difference is measured using a voltmeter, which is a device that measures the potential difference between two points in an electric circuit. It is typically connected in parallel with the component or circuit being measured.

## 5. What are some real-life applications of electric potential difference?

Electric potential difference is the basis for all electrical circuits and is essential for the functioning of electronic devices. It is also used in power generation and distribution, as well as in medical devices such as pacemakers and defibrillators. Electric potential difference is also important in electroplating, electrolysis, and other chemical processes.

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