Understand how much distance I have to move to cause a voltage difference of 1 V
a) Far away from the source charge b) Very close to the source charge.
Connect that finding with Conservative Force / Field concepts
Equipotential Lines for two charges separated by a distance
$E= - \frac{dV}{dr} \; \; F = -\frac{dU}{dr}$
a) oppositely charged b) same charged
Capacitor Basics
Change the battery voltage and see what happens to
the charge and the voltage in the capacitor, Q = C V
Change the area and gap between the plates and see what happens
to the Capacitance value, C = epsilon_o A / d