1. Notice that the field lines are straight inside the capacitor but curved at the ends. These regions of curved field lines are known as fringe fields. Explain why you would expect the field lines to curve at the ends.
2. In your textbook you will be able to find the equation for the capacitance of a parallel-plate capacitor. Use this and what you know about the geometry of the capacitor in the simulation to determine the magnitude of the charge on each plate. Now change the distance between the plates in the simulation. Does this change the amount of charge on each plate? Does this help explain the difference in the electric field you measure at the center of the capacitor in each case?