Net Electric Field: +q1 -q2 Spot at 0 E

[ptdreamer]

A positive charge of +q1 is located 5.22 m to the left of a negative charge -q2. The charges have different magnitudes. On the line through the charges, the net electric field is zero at a spot 2.55 m to the right of the negative charge. On this line there are also two spots where the potential is zero. (a) How far to the left of the negative charge is one spot? (b) How far to the right of the negative charge is the other?


E= kq1/5.22^2m + k(-q)/2.55^2m = 0
I think that this is the first equation that I use. I am not sure if I have set it up right.

and then I use this equation I think.
kq1/x1+ k(-q)/5.22-x1=0?

Overall, I just need someone to clarify PLEASE!

 

[tiny-tim]

Hi ptdreamer!

E= kq1/5.22^2m + k(-q)/2.55^2m = 0
I think that this is the first equation that I use. I am not sure if I have set it up right.

and then I use this equation I think.
kq1/x1+ k(-q)/5.22-x1=0?

Overall, I just need someone to clarify PLEASE!

Yes, that's all good, but of course it only gives you one of the spots …

how should you adjust the second equation to get the other one?

 

[thomate1]

I can confirm that the equations you have set up are correct and are a good starting point for solving this problem. However, it is important to note that the net electric field is zero at a spot between the two charges, not necessarily at the spot 2.55 m to the right of the negative charge. This means that the distance x1, which represents the distance from the negative charge to the first spot where the net electric field is zero, is not necessarily 2.55 m.

To solve for the distance x1, you can set up the equation as follows:

kq1/x1^2 + k(-q)/(5.22-x1)^2 = 0

This equation represents the balance between the electric field created by the positive charge at a distance x1 and the electric field created by the negative charge at a distance 5.22-x1. By setting the sum of these two electric fields equal to zero, we can solve for the distance x1.

Similarly, to solve for the distance x2, which represents the distance from the negative charge to the second spot where the potential is zero, you can set up the following equation:

kq1/x2 + k(-q)/(5.22+x2)^2 = 0

This equation represents the balance between the potential created by the positive charge at a distance x2 and the potential created by the negative charge at a distance 5.22+x2. By setting the sum of these two potentials equal to zero, we can solve for the distance x2.

Once you have solved for both x1 and x2, you can use these values to answer the questions of how far to the left and right of the negative charge the two spots are located. I hope this helps clarify the problem for you.