How to understand the concept of work using the following example:
a positively charged particle (with charge $Q$) is placed in between a charged in a homogeneous electric field between the capacitor plates. This charged particle is placed close to the positive plate.
When this particle is released at P1, then the electric force acting upon it (to the right) will cause it to accelerate to the right. Therefore its kinetic energy will increase. This tells me that the charge had a greater Potential Energy at the start (P1).
However I am confronted with the idea that the system as a whole has done negative work, because we did not do anything (no exterior influences/forces) in order to move the particle. Could someone explain to me why this is the case?