Hello!
Work is equal to the change in KE or the negative change in PE. So if e field is directed vertically upward or in positive y direction and our charge is positive it’s going to move in direction of e field so then the work done by the e field is negative because it is losing potential energy the farther it moves upward away from field. Work=qed which is charge*e field*distance travelled.
Hope this helps! Any questions please ask! Thank you!!
