# #

A parallel-plate capacitor has charge of magnitude $$\rm\ \mu\textrm{C}$$ on each plate and capacitance $$\rm\ \mu\textrm{F}$$ when there is air between the plates. The plates are separated by $$\textrm{ mm}$$. With the charge on the plates kept constant, a dielectric with $$\kappa =$$ is inserted between the plates, completely filling the volume between the plates.

## Part 1#

What is the potential difference between the plates of the capacitor before the dielectric has been inserted?

## Part 2#

What is the potential difference between the plates of the capacitor after the dielectric has been inserted?

## Part 3#

What is the electrical field at the point midway between the plates before the dielectric is inserted?

## Part 4#

What is the electrical field at the point midway between the plates after the dielectric is inserted?