Electric Potential: Find x for Zero Net Electric Potential

Click For Summary

Homework Help Overview

The problem involves determining the positions along the x-axis where the net electric potential due to two fixed charges, q1 and q2, is zero. The charges are separated by a distance of d, and the context includes understanding the implications of electric potential and field strength in relation to these charges.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants discuss the significance of the positions considered for x, particularly questioning why x is not taken to be greater than d. There is a focus on the relationship between electric fields and potentials, with some participants exploring the reasoning behind the locations where the net potential is zero.

Discussion Status

The discussion is ongoing, with participants offering insights into the nature of electric fields and potentials. Some guidance has been provided regarding the behavior of the electric fields in relation to the charges, but multiple interpretations of the problem are being explored without a clear consensus.

Contextual Notes

There is a noted assumption regarding the regions where the potential is considered, specifically the implications of evaluating x in relation to the distance d between the charges. Participants are also navigating the differences between electric field and potential calculations.

Air
Messages
202
Reaction score
0

Homework Statement


Particles of the charges q1=+5e (at origin) and q2=-15e are fixed in place with a separation of d=0.24m. With V=0 at infinity, what are the finite (a) positive and (b) negative values of x at which the net electric potential on the x-axis is zero?


Homework Equations


E=Kq/r


3. The problem I encounter
I can get the answer but I don't understand the position considered. Where do I consider my x value to be? Why don't we consider x to be greater than d? Why do we only consider for 0<x<d or x<d?
 
Physics news on Phys.org
x is the point where the electric fields from the charges cancel each other out. There are only two such points. You can consider x>d if you like but you won't find a point where the fields cancel each other because the field of q2 is always stronger in that region.
 
But we are considering potential. Do we understand through electric field then use the equation of potential?
 
Well, the only difference in the formula for the field is the power of r so qualitatively it's the same. In the region x>d the magnitude of q2 potential is always greater than that of q1. I just thought fields are more intuitive and illustrate better why there are only two points.
 

Similar threads

Replies
19
Views
3K
Replies
5
Views
3K
  • · Replies 20 ·
Replies
20
Views
3K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 7 ·
Replies
7
Views
4K