An isolated large-plate capacitor (not connected to anything) originally has a potential difference of 1000 volts with an air gap of 2 mm. Then a plastic slab 1 mm thick, with dielectric constant 5,...

An isolated large-plate capacitor (not connected to anything) originally has a potential difference of 1000 volts with an air

gap of 2 mm. Then a plastic slab 1 mm thick, with dielectric constant 5, is inserted into the middle of the air gap as shown

in Figure 17.94. Calculate the following potential differences, and explain your work.