Now, my question is, how do we get this electron not a distance our way, but a distance to our way? In other words, how do we move this electron from this guy from this distance to this distance? Well, remember, if this is a positive force and this is a negative force, these guys are tracting. They want to come close. So in order for me to move this guy a distance R here a distance two R from our nucleus. That means I have to do work on that electron.