If I have a dielectric (a piezoelectric, to be exact) sandwiched between two platinum plates (electrodes), and connect one end to positive potential of a battery and the other to ground (I don't even know why one has to connect the top to ground), and also connect the negative potential of a battery to ground, what is the electric field on the surface of the grounded plate? Where do the field lines coming from the bottom plate terminate?
I ask because I'm doing an experiment where I'm trying to put particles on top of an electrode on a piezoelectric plate to stretch them. The particle is field-sensitive (sensitive to electric fields) so I thought if I just ground the plate the particles are on, everything would be fine. However, just because the plate is at zero potential (grounded), does that mean the field on its surface is zero?