1. The problem statement, all variables and given/known data A 0.010-kg positively-charged particle is accelerated by a uniform electric field directed to the right. The object accelerates from 5.0 to 15.0 m/s while traveling a distance of 0.10 m. Suppose the particle is moved by an external force a distance of 0.10 m against the field. What is the change in electric potential energy of the particle? Is the change an increase or a decrease? 2. Relevant equations DeltaU = -W W=fd 3. The attempt at a solution I know that Fext must be greater than Fel, but how much greater? W=fd, distance is .10m. How do I determine the change in EPE, specifically calculating the amount of work neccesary?