# E&M potential difference

1. Mar 7, 2016

### PhysicsInNJ

1. The problem statement, all variables and given/known data
The electric field in a region of space has the components Ey = Ez = 0 and Ex = (4.00 N/C·m) x. Point A is on the y axis at y = 3.60 m, and Point B is on thex axis at x = 3.00 m. What is the potential difference VBVA?

2. Relevant equations
Vb- Vi = -∫ba E * dS

3. The attempt at a solution
The integral should become E*d, or 4*0.6 , but that is incorrect

2. Mar 7, 2016

### Staff: Mentor

Where does the 0.6 come from? Note that the two points are on different axes.

3. Mar 8, 2016

### rude man

What's a good choice of path integration? Does the datum y = 3.6, as opposed to some other y number, have any significance?

4. Mar 8, 2016

### vela

Staff Emeritus
In addition to what the others said, $\Delta V = Ed$ only holds for uniform fields. You don't have a uniform field in this problem.