Electric potential at point from origin

[rlaulusa]

Homework Statement

In the presence of a uniform electric field, E=-6.0 i + .8 j + 3.42 k N/C, assume that the electric potential is -5V at the origin of the coordinate system, and determine the electric potential at the point 2.7 i -2.7 k.


Here's what I've done so far
\DeltaV=V(2.7, 0, -2.7) - V(0, 0, 0,) = \intEds
=-(\int^{2.7}_{0}Exdx + \int^{0}_{0}Eydy + \int^{-2.7}_{0}Ezdz)
=-(\int-6.9dx + \int.8dy + \int3.42dx)
=3.48 V

But I don't think this is correct. We did a problem similar to this in class where we had to define the path we were taking, but I wasn't sure how to do that in this problem.

Thanks!

 

[gneill]

The field is stated to be uniform, so the potential should change uniformly per unit distance in a given direction. A straight path from the origin p0 = (0,0,0) to your destination p1 = (2.7,0,-2.7) should do nicely, with the change in potential being given by the dot product E dot (p1 - p0). Don't forget to include the given starting potential at the origin. You should also state the units of measure for the distances!