Electric field and equipotential lines

In summary,1) Parallel plate capacitors have fields and equipotential lines. Equipotential lines have no direction, while field lines show direction from the + to the - plate.2) Near the edges of the plates, the electric field becomes distorted, and is not a uniform field.3) If you have a positively charged plate and place a negatively charged point charge above it, the electric field on them becomes less intense and non-uniform.
  • #1
twiztidmxcn
43
0
just a coupla quick questions:

1) in a parallel plate capacitor, we have field lines and equipotential lines. field lines show direction from the + to the - plate, but equipotential lines have no direction. why is this?

2) what happens to the electric field near the edges of the plates?

3) if you have a positively charged plate and place a negatively charged point charge above it, what does the electric field look like on them?

for part 1, i know that field lines have direction because it is an electric force acting in a certain direction, but I am not too sure about this equipotential stuff. i figure that the equipotential lines have no direction because they have no force acting on them at those points, I'm not too sure though...

for part 2, i know that between the plates the field is uniform and the strongest, so at the edge of the plates it becomes less intense and non-uniform?

for part 3, i know field lines go from + to - charges, but this is a plate and all the E lines radiate out from it, I am not sure if they all just go into the negative charge or what the deal is really
i dunno, any help would be appreciated
-twiztidmxcn
 
Last edited:
Physics news on Phys.org
  • #2
1. Equipotentials simply connect all the points that have the same potential energy (if a particle was there), and so you can move along them and do no work, and as such have no associated direction (unlike field lines).

2. Towards the edges of the plates, the eletric field becomes a little distorted, and so technically isn't a uniform field, so yes you are right.

for part 3, i know field lines go from + to - charges, but this is a plate and all the E lines radiate out from it, I am not sure if they all just go into the negative charge

3. I think that the E lines do because the positive and the negative attract.
 
  • #3
twiztidmxcn said:
just a coupla quick questions:

1) in a parallel plate capacitor, we have field lines and equipotential lines. field lines show direction from the + to the - plate, but equipotential lines have no direction. why is this?

2) what happens to the electric field near the edges of the plates?

3) if you have a positively charged plate and place a negatively charged point charge above it, what does the electric field look like on them?

for part 1, i know that field lines have direction because it is an electric force acting in a certain direction, but I am not too sure about this equipotential stuff. i figure that the equipotential lines have no direction because they have no force acting on them at those points, I'm not too sure though...

for part 2, i know that between the plates the field is uniform and the strongest, so at the edge of the plates it becomes less intense and non-uniform?

for part 3, i know field lines go from + to - charges, but this is a plate and all the E lines radiate out from it, I am not sure if they all just go into the negative charge or what the deal is really
i dunno, any help would be appreciated
-twiztidmxcn

One or two comments to add to finchie_88's post.

Equipotential lines mark the value of the electric potential, which is a scalar quantity, so we would expect no direction to be associated with it. Electric fields are vectors, so we would want to know a direction.

Depends on what you mean by "edges." Macroscopically, which is what I assume you are talking about (as opposed to quantum), when an electric field line meets a conductor the electric field is perpendicular to the conductor. If you are talking about a corner, all H*ll breaks loose. Field lines tend to congregate around points so the corners can be rather packed with field lines. The sharper the point, the more intense in general. (There is, of course, a limit to that depending on the overall energy of the field.) This is essentially how a lightning rod works...they come to a point, so the lightning, which is a flow of charged particles, tends to be attracted more to that point.

-Dan
 

1. What is an electric field?

An electric field is a physical field that is created by electrically charged particles, such as electrons or protons. It is responsible for the force that electrically charged particles experience, and is typically represented by arrows that point in the direction of the force.

2. How do I calculate the strength of an electric field?

The strength of an electric field can be calculated by dividing the force experienced by a charged particle by the magnitude of the charge of the particle. This can be expressed mathematically as E = F/q, where E is the electric field strength, F is the force, and q is the charge of the particle.

3. What are equipotential lines?

Equipotential lines are imaginary lines that connect points with the same electric potential. This means that if a charged particle were to move along an equipotential line, it would experience no change in its potential energy. These lines are always perpendicular to electric field lines.

4. How do I draw equipotential lines?

To draw equipotential lines, you must first determine the electric field lines at the points where you want to draw the equipotential lines. Then, draw the equipotential lines perpendicular to the electric field lines, making sure that they do not intersect. The spacing between equipotential lines should be equal, indicating that the potential difference between each line is the same.

5. What is the relationship between electric field and equipotential lines?

Electric field lines and equipotential lines are always perpendicular to each other. This means that they intersect at right angles. Additionally, equipotential lines are always perpendicular to the direction of the electric field, indicating that the electric field is strongest where the equipotential lines are closest together.

Similar threads

  • Advanced Physics Homework Help
Replies
4
Views
3K
  • Introductory Physics Homework Help
Replies
3
Views
972
  • Advanced Physics Homework Help
Replies
3
Views
2K
  • Introductory Physics Homework Help
Replies
11
Views
275
  • Advanced Physics Homework Help
Replies
7
Views
991
  • Introductory Physics Homework Help
Replies
7
Views
898
  • Advanced Physics Homework Help
2
Replies
69
Views
3K
  • Advanced Physics Homework Help
Replies
2
Views
1K
  • Advanced Physics Homework Help
Replies
17
Views
1K
  • Advanced Physics Homework Help
Replies
13
Views
2K
Back
Top