Independent of Test Charge?
To move a charge in an E field, we must supply a force just equal and opposite to that experienced by the charge due to the E field.
Remember: work is force times distance
http://wug.physics.uiuc.edu/courses/phys112/fall97/acts/lect05/act05a/sld001.htm
- The overall sign of this: A positive charge would “fall” from a higher potential to a lower one
- to get a positive test charge from the lower potential to the higher potential you need to invest energy - you need to do work