Electric potential Energy/ electric potential

In summary: I think I got it now. thanks!In summary, an electric potential is due to an external electrostatic field, while an electric potential energy is due to a test charge that resides within that field.
  • #1
Ksingh30
11
0
Can some please explain the difference between "Electric potential Energy & electric potential" and when a problem is asking you to find the potential difference which is it asking for?
 
Physics news on Phys.org
  • #2
Ksingh30 said:
Can some please explain the difference between "Electric potential Energy & electric potential" and when a problem is asking you to find the potential difference which is it asking for?
Potential is just the amount of potential energy per unit of charge,
thus for a point charge with charge q and potential energy U

[tex] V = \frac{U}{q} [/itex]

Another way of saying this is that V is the potential energy a point charge of 1C would have.

As you know the change in potential energy [itex] \Delta U [/itex] can be used to find the amount of work done by a conservative force.

Thus [itex] \Delta V [/itex] tells us the amount of work done per unit of charge by an electric field.

Or again, another way of saying this is that [itex] \Delta V [/itex] is the amount of work done on a point charge of 1C by an electric field.
 
  • #3
wow

im still confused. I don't understand. This is the first topic in physics so far that has me confused.
 
  • #4
which part confuses you?
Do you know what potential energy is? If not then potential won't make any sense no matter how its explained.
 
  • #5
oh wait

I think I just got it. correct me if I am wrong please. if a charge enters a uniform electric field and it moves from point A to point B. The work done to move it from point Ato B=FD(distance moved), and if the charge moved towards the Low PE. it gained kinetic energy therefore it lost PE. so the change in PE(electric potential)=-W(work done to move from A to B)= -FD. and then the potential diference (V). the chance in V= change in PE/ q(the charge)
well?
 
  • #6
charge

im assuming the charge is positive
 
  • #7
Ksingh30 said:
I think I just got it. correct me if I am wrong please.
a few corrections but for the most part your right., my corrections are in bold

if a charge enters a uniform electric field and it moves from point A to point B. The work done to move it from point Ato B=FD(distance moved), and if the charge moved towards the Low PE. it gained kinetic energy therefore it lost PE(side note: if the charge moved to a position with less PE that means it lost potential energy. ). so the change in PE(electric potential energy)=-W(work done by the electric field to move from A to B )= -FD. and then the potential diference (V). the chance in V= change in PE/ q(the charge)
well?

This is one very specific example
 
  • #8
With no intention to confuse you further (believe me mate, this can really kill you if you don't do it properly...) I'd like to add that in most texts, the external agent applies a force on the charge which is equal and opposite to the electrostatic force on it. This is because it is desired that the object be moved with zero acceleration. This is a very essential idea in electrostatics and you'll use it (sometimes unconsciously) in future.
 
  • #9
Ksingh30 said:
Can some please explain the difference between "Electric potential Energy & electric potential" and when a problem is asking you to find the potential difference which is it asking for?

Just to add to what has been said here, an "electric potential" is due to the "field", whereas an "electric potential energy" is due to some test charge IN that field.

Let's say something somewhere creates an electrostatic field. Then the electric potential is the potential at some location in space due to this field. Only when you put a test charge Q at that location, is there now an electric potential energy, since you can now make a statement about work done in moving that charge from a 0 potential reference point to that location.

Notice that we are saying nothing about the field generated by Q itself. Q is simply a test charge residing within this already-created external field. [Q interacting with its own field is what is crudely defined as the self-energy interaction]

Zz.
 

1. What is electric potential energy?

Electric potential energy is the energy that a charged particle possesses due to its position in an electric field. It is the potential for a charged particle to do work by moving from one point to another in an electric field.

2. How is electric potential energy different from electric potential?

Electric potential energy is a measure of the potential for a charged particle to do work, while electric potential is a measure of the potential energy per unit charge at a specific point in an electric field.

3. How is electric potential energy calculated?

Electric potential energy is calculated using the equation U = qV, where U is the potential energy, q is the charge of the particle, and V is the electric potential at the point where the particle is located.

4. What is the unit for electric potential energy?

The unit for electric potential energy is joules (J), which is also the unit for all forms of energy.

5. How is electric potential energy related to electric potential difference?

Electric potential energy and electric potential difference are related through the equation U = qΔV, where ΔV is the change in electric potential between two points. This means that the greater the change in electric potential, the greater the change in electric potential energy for a charged particle.

Similar threads

Replies
22
Views
1K
  • Introductory Physics Homework Help
Replies
6
Views
218
  • Introductory Physics Homework Help
Replies
7
Views
280
  • Introductory Physics Homework Help
Replies
3
Views
457
  • Introductory Physics Homework Help
Replies
5
Views
840
  • Introductory Physics Homework Help
Replies
23
Views
257
  • Introductory Physics Homework Help
Replies
6
Views
721
  • Introductory Physics Homework Help
Replies
2
Views
250
  • Introductory Physics Homework Help
Replies
9
Views
311
  • Introductory Physics Homework Help
Replies
9
Views
801
Back
Top