Finding the potential difference given two unknown points.

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SUMMARY

The discussion focuses on calculating the potential difference between two points in a Cartesian coordinate system using the formula v=k(q2)/r2-k(q1)/r1. The user has defined the positions of two charges, q1 at (1,0) and q2 at (-1,0), both with a magnitude of one. The user explores the implications of setting v to zero, concluding that the points of equal potential lie along the y-axis. The user seeks guidance on manipulating the equation to derive a general form for the potential difference.

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  • Understanding of electrostatics, specifically potential difference calculations.
  • Familiarity with Cartesian coordinates and distance formulas.
  • Knowledge of algebraic manipulation and solving equations.
  • Basic principles of electric fields and forces.
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  • Study the concept of electric potential and its relation to electric fields.
  • Learn about the method of superposition in electrostatics.
  • Explore the implications of potential difference in different coordinate systems.
  • Investigate graphical methods for visualizing electric potentials in two dimensions.
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Students in physics, particularly those studying electrostatics, as well as educators seeking to understand potential difference calculations in a Cartesian framework.

rslewis96
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Homework Statement


I am trying to determine at what points the given potential difference will be using v=k(q2)/r2-k(q1)/r1.

I know the location of both q1 and q2 using cartesian coordinates, as well as, there magnitudes which I have set each to one.
q1=(1,0)
q2=(-1,0)

Homework Equations


v=kq/r,
Vba=Vb-Va
Vb=k(q2)/r2
Va=k(q1)/r1
v=k(q2)/r2-k(q1)/r1
r1=sqrt((x1-x0)^2+(y1-y0)^2)
r2=sqrt((x2-x0)^2+(y2-y0)^2)

The Attempt at a Solution


First I found that if you set v=0, then the points will be right along the y-axis.

r2=r1

Which this makes sense given that each point is a equal distance from each other along the x-axis.
Next I tried to see if I could determine the points given that v>0 or v<0. How I wanted to proceeded was to create a general form of an equation, such as x0=whatever*y0 or y0=whatever*x0. This would allow me to create an x,y table and plug in for one variable to find the other.

My first thought was to get the content within both r1 and r2 out of the square root. I started by squaring both r1 and r2. I then needed to get the equation v=k(q2)/r2-k(q1)/r1 having even powers of r1 and r2.

Here is my attempt:
(v/k)=(1/r2-1/r1) => (r1*r2)(v/k)=(r1-r2) => ((r1*r2)(v/k))^2=(r1^2-2r1r2+r2^2) => (((r1*r2)(v/k))^2)-r1^2-r2^2=-2r1r2

=> [((r1*r2)(v/k))^2-r1^2-r2^2]^2=(-2r1r2)^2

I tried to work with this equation, but got nowhere.

I am not sure if I am going in the wrong direction completely or what. I'm not looking for anyone to solve this for me, I am looking for advice on how to proceed. Any advice will be helpful.

Thank you for your time.
 
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